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Sample records for algerian septentrional sahara

  1. Crop drying by indirect active hybrid solar - Electrical dryer in the eastern Algerian Septentrional Sahara

    Energy Technology Data Exchange (ETDEWEB)

    Boughali, S.; Bouchekima, B.; Mennouche, D.; Bouguettaia, H.; Bechki, D. [Laboratory of New and Renewable Energy in Aride Zones, University Kasdi Merbah, BP511 Ouargla (Algeria); Benmoussa, H. [Faculty of Science, Department of Mechanics, University Hadj Lakhdar, Batna (Algeria)

    2009-12-15

    In the present work, a new specific prototype of an indirect active hybrid solar-electrical dryer for agricultural products was constructed and investigated at LENREZA Laboratory, University of Ouargla (Algerian Sahara). In the new configuration of air drying passage; the study was done in a somewhat high range of mass flow rate between 0.04 and 0.08 kg/m{sup 2} s a range not properly investigated by most researchers. Experimental tests with and without load were performed in winter season in order to study the thermal behavior of the dryer and the effect of high air masse flow on the collector and system drying efficiency. The fraction of electrical and solar energy contribution versus air mass flow rate was investigated. Slice tomato was studied with different temperatures and velocities of drying air in order to study the influence of these parameters on the removal moisture content from the product and on the kinetics drying and also to determine their suitable values. Many different thin layer mathematical drying models were compared according to their coefficient of determination (R{sup 2}) and reduced chi square ({chi}{sup 2}) to estimate experimental drying curves. The Middli model in this condition proved to be the best for predicting drying behavior of tomato slice with (R{sup 2} = 0.9995, {chi}{sup 2} = 0.0001). Finally an economic evaluation was calculated using the criterion of payback period which is found very small 1.27 years compared to the life of the dryer 15 years. (author)

  2. Les espèces médicinales spontanées du Sahara septentrional ...

    African Journals Online (AJOL)

    The spontaneous plants of the Sahara are very feature by their fashion of adaptation individual to the very coercive desert environment to their survival. To short come our spatio-temporal survey of 5 years (2000- 2005), we put in evidence the existence of 5 different geomorphologic zones, in which we inventoried 130 ...

  3. Microbial Diversity of the Hypersaline Sidi Ameur and Himalatt Salt Lakes of the Algerian Sahara

    OpenAIRE

    Boutaiba, Saad; Hacene, Hocine; Bidle, Kelly A.; Maupin-Furlow, Julie A.

    2011-01-01

    Microbial populations within hypersaline lakes often exhibit high activities of photosynthesis, dissimilatory sulphate reduction and other processes and, thus, can have profound impacts on biogeochemical cycles of carbon, nitrogen, sulphur and other important elements within arid lands. To further understand these types of ecosystems, the physicochemical and biological properties of Sidi Ameur and Himalatt Salt Lakes in the Algerian Sahara were examined and compared. Both lakes were relativel...

  4. Microbial diversity and organic matter fractions under two arid soils in Algerian Sahara

    Science.gov (United States)

    Karabi, Mokhtar; Hamdi, Aissa Baelhadj; Zenkhri, Salah

    2016-07-01

    The Algerian Sahara is characterized by a heterogeneity of edaphic conditions and climatic dissimilarities; however, information on biological indicators of arid soils is weakly documented in this area. The researchers who have studied the biological activities of the soils of the arid regions have underlined their low organic matter content, particularly their very low rates of organic nitrogen; a low humification because seriously inhibited by a significant mineralization. The objective of the current work is to study the microbial biomass densities and organic matter fractions for different types of soil, under two arid soil in Algerian Sahara. The experiment was conducted in an alluvial soil in traditional palm grove of Guerrara, and in a saline soil in experimental field of university of Ouargla. Composite soil samples (10 subsamples each) were collected aseptically at 0-20 cm depth on two diagonal transects drawn over an area of 12 ha. The following germs densities were determined: Bacteria, Fungi and Actinomycetes. The soil organic matter fractions, the textural fractions, chemical attributes (organic C, total N, total limestone and gypsum) were also determined. The microbial groups count on both soils reveals that the bacterianmicroflora present a numerical superiority followed by the actinomycetes and finally fungi. The micro-organisms densities except fungal density, showed a prevalence of the bacterianmicroflora, and actinomycetes in alluvial soil compared to saline soil. Fractionation of soil organic matter show that all fractions are better represented in alluvial soil except non-extractable organic carbon (NEOC) which are better represented in saline soil. This confirms that alluvial soil has a relatively large biological activity than saline soil and that humification process is relatively pronounced by comparing it with the saline soil, which tends to contain little polycondenseshumic compounds.

  5. Microbial Diversity of the Hypersaline Sidi Ameur and Himalatt Salt Lakes of the Algerian Sahara.

    Science.gov (United States)

    Boutaiba, Saad; Hacene, Hocine; Bidle, Kelly A; Maupin-Furlow, Julie A

    2011-10-01

    Microbial populations within hypersaline lakes often exhibit high activities of photosynthesis, dissimilatory sulphate reduction and other processes and, thus, can have profound impacts on biogeochemical cycles of carbon, nitrogen, sulphur and other important elements within arid lands. To further understand these types of ecosystems, the physicochemical and biological properties of Sidi Ameur and Himalatt Salt Lakes in the Algerian Sahara were examined and compared. Both lakes were relatively neutral in pH (7.2 to 7.4) and high in salt, at 12% and 20 % (w/v) salinity for Himalatt and Sidi Ameur Lakes, respectively, with dominant ions of sodium and chloride. The community compositions of microbes from all three domains (Bacteria, Archaea and Eukarya) were surveyed through the use of 16S and 18S ribosomal gene amplification and clone library clustering using amplified ribosomal DNA restriction analysis (ARDRA) in conjunction with DNA sequencing and analysis. A high level of microbial diversity, particularly among the bacteria of the Himalatt Salt Lake and archaea of Sidi Ameur Lake, was found within these environments. Representatives from all known halophilic bacterial phyla as well as 6 different genera of halophilic archaea were identified. Moreover, several apparently novel phylotypes among both archaea and bacteria were revealed.

  6. Carboniferous bioconstructions of the Bechar Basin, Algerian Sahara: Sedimentology, diagenesis, and petroleum potential. Les bioconstructions carboniferes du Bassin de Bechar, Sahara algerien: Sedimentologie, diagenese et potentiel petrolifere

    Energy Technology Data Exchange (ETDEWEB)

    Madi, A.

    1994-01-01

    Carbonate massifs which surface on the northwest of the Bechar Basin in the Algerian Sahara are studied, in particular the lithostratigraphic section of the upper Visean of the Grand Erg Occidental. The latter corresponds to a succession of 13 shallowing-upward parasequences. An ideal parasequence comprises a massive biohermal assemblage, constructed by the association of Fenestelles and sponges, buried under strata of crinoidal and/or oolithic grainstones. The vertical distribution of the microflora within the facies translates into a zonation as function of depth. An idealized ecological succession formed from seven benthic assemblages is proposed. Diagenetic analysis of the studied sequences has revealed nine diagenetic phases corresponding to six calcitic cements, two dolomitization phases, and one of silicification. Most of these diagenetic events were produced in medium to deep burial, after 650 m. The stratified oolithic-crinoidal carbonates could have served as reservoir rocks if trapping conditions were present. A hypothesis has been formed according to which the porous strata formed natural conduits on a regional scale and three trapping possibilities are proposed. These models, which integrate all the parameters which influence the existence of a petroleum deposit, could contribute to the establishment of an exploration strategy for the Bechar Basin Carboniferous carbonate strata. 146 refs., 61 figs., 29 tabs.

  7. Tin Zaouatine: A full solar energy village in the Algerian Sahara

    International Nuclear Information System (INIS)

    Labed, S.; Yaici, B.

    1991-01-01

    The photovoltaic (PV) electrification of the title village is part of a wide solar energy program sponsored by the Algerian government. A description is given of the realization of phase 1 of the project, achieved in February 1990. Phase 1 covers 80% of the energy demand of the village and comprises 8 PV installations (AC power), 10 small PV installations (kits-DC power), and 2 PV pumping systems (DC power) for drinking water only. After a brief description of the village attention is paid to the design approach, the social aspects, the problems encountered, the experiments gained and some initial results. 1 fig., 1 tab., 2 refs

  8. Screening for Genes Coding for Putative Antitumor Compounds, Antimicrobial and Enzymatic Activities from Haloalkalitolerant and Haloalkaliphilic Bacteria Strains of Algerian Sahara Soils

    Directory of Open Access Journals (Sweden)

    Okba Selama

    2014-01-01

    Full Text Available Extreme environments may often contain unusual bacterial groups whose physiology is distinct from those of normal environments. To satisfy the need for new bioactive pharmaceuticals compounds and enzymes, we report here the isolation of novel bacteria from an extreme environment. Thirteen selected haloalkalitolerant and haloalkaliphilic bacteria were isolated from Algerian Sahara Desert soils. These isolates were screened for the presence of genes coding for putative antitumor compounds using PCR based methods. Enzymatic, antibacterial, and antifungal activities were determined by using cultural dependant methods. Several of these isolates are typical of desert and alkaline saline soils, but, in addition, we report for the first time the presence of a potential new member of the genus Nocardia with particular activity against the yeast Saccharomyces cerevisiae. In addition to their haloalkali character, the presence of genes coding for putative antitumor compounds, combined with the antimicrobial activity against a broad range of indicator strains and their enzymatic potential, makes them suitable for biotechnology applications.

  9. The effects of the final stages of the Late Ordovician glaciation on marine palynomorphs (chitinozoans, acritarchs, leiospheres) in well Nl-2 (NE Algerian Sahara).

    Science.gov (United States)

    Paris, F; Bourahrouh, A; Hérissé, A L.

    2000-12-01

    Palynomorph assemblages, especially chitinozoans and acritarchs, from the Upper Ordovician of well Nl-2 (north-east of the Algerian Sahara) are studied in order to precisely date the ultimate effects of the Late Ordovician glaciation and to document the impact of this major climatic stress on the diversity of the palynoplankton. References are made to stable isotope excursions and to global eustatic sea level variations in order to improve the local age determination. The Hassi el Hadjar Formation, i.e. glacio-marine diamictites, is interpreted as a transgressive event resulting from the melting of the northern Gondwana ice cap. It yields poorly preserved and moderately diverse chitinozoans of late Hirnantian age. Acritarchs are more abundant in the lower part of these "microconglomeratic clays", but display a low diversity and are badly preserved throughout the whole formation. Reworked individuals are recorded in both groups. The marine sediments of the M'Kratta Formation of latest Hirnantian age contain better preserved, more abundant and more diverse palynomorph assemblages, especially in the Upper Member. The composition of this palynoplankton indicates a fairly good faunal and phytoplankton recovery after the early Hirnantian climatic stress.The extinction of the Ordovician forms, and the appearance of Silurian type taxa occur only in the uppermost Hirnantian, i.e. following with a slight delay the glacial event. The overlying black shales of Wenlock age (lower part of the Oued Mehaiguène Formation) are indicative of marine anoxic environments. They yield a virtually exclusive, but enormous number of Tasmanacea. The very peculiar composition of this palynoplankton seems to be independent of the Late Ordovician glaciation and is most likely related to the factors that, later, generated and maintained anoxic conditions in this area.A new species of chitinozoan, Spinachitina oulebsiri sp. nov. from the latest Hirnantian M'Kratta Formation, is described and

  10. Impact de la dynamique de l’agriculture et ses conséquences sur la durabilité de l’écosystème saharien : cas de la vallée de M’zab (Sahara septentrional

    Directory of Open Access Journals (Sweden)

    Hocine BENSAHA

    2016-12-01

    Full Text Available Like other Saharan regions, the Algerian development program of agricultural land has increased agricultural area in the valley of M’Zab. Creating development zones in the Valley of M’zab generated some momentum with a series of measures with different impacts on the components of this agro-ecosystem. Its dynamics have shown particular shortcomings at different levels thus compromising durability. The measures to be taken are justified not only to preserve the ecosystem but also to give meaning to the strong investments made by public authorities.

  11. Sustainable Development of the Algerian Steppe | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sustainable Development of the Algerian Steppe. The Algerian steppe covers more than 30 million ha of land and constitutes a buffer zone between the Sahara Desert and the green belt in the North. The diversity and relative abundance of fodder plants has allowed the steppe to provide livelihoods for 15% of the ...

  12. Sustainable Development of the Algerian Steppe | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The Algerian steppe covers more than 30 million ha of land and constitutes a buffer zone between the Sahara Desert and the green belt in the North. The diversity and relative abundance of fodder plants has allowed the steppe to provide livelihoods for 15% of the population and the main source of red meat for the ...

  13. Total and the Algerian shale gas

    International Nuclear Information System (INIS)

    Chapelle, Sophie; Petitjean, Olivier; Maurin, Wilfried; Balvet, Jacqueline; Combes, Maxime; Geze, Francois; Hamouchene, Hamza; Hidouci, Ghazi; Malti, Hocine; Renaud, Juliette; Simon, Antoine; Titouche, Fateh

    2015-01-01

    This publication proposes a rather detailed and discussed overview of the movement of mobilisation of Algerian people (notably those living in the Sahara) against projects of exploration and exploitation of shale gases in Algeria by the Total group. The authors also recall and comment the long and heavy history of hydrocarbon management in Algeria, the role of international firms and of western interests (notably French interests) in this country, and the position of Total regarding the stake related to shale gases. The authors outline problems created by shale gas exploitation regarding water consumption and waste waters. They also notice that the safety of wells is at the centre of the protest. Problems raised by hydraulic fracturing are reviewed: seismic activity, chemical pollution, air pollution and greenhouse gases, landscape destruction. The attitude of the Algerian government is commented. Then, the authors try to identify and describe the action of Total in the Algerian shale gas sector, discuss the possible French influence, and outline the presence of Total all over the world in this sector

  14. Reconstruction of exposure histories of meteorites from Antarctica and the Sahara

    International Nuclear Information System (INIS)

    Neupert, U.; Neumann, S.; Leya, I.; Michel, R.; Kubik, P.W.; Bonani, G.; Hajdas, I.; Suter, M.

    1997-01-01

    10 Be, 14 C, and 26 Al were analyzed in H-, L-, and LL-chondrites from the Acfer region in the Algerian Sahara and from the Allan Hills/Antarctica. Exposure histories and terrestrial ages could be determined. (author) 3 figs., 2 refs

  15. Reconstruction of exposure histories of meteorites from Antarctica and the Sahara

    Energy Technology Data Exchange (ETDEWEB)

    Neupert, U.; Neumann, S.; Leya, I.; Michel, R. [Hannover Univ. (Germany). Zentraleinrichtung fuer Strahlenschutz (ZfS); Kubik, P.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Bonani, G.; Hajdas, I.; Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    {sup 10}Be, {sup 14}C, and {sup 26}Al were analyzed in H-, L-, and LL-chondrites from the Acfer region in the Algerian Sahara and from the Allan Hills/Antarctica. Exposure histories and terrestrial ages could be determined. (author) 3 figs., 2 refs.

  16. inventory of arthropods on sesbania acuelata in the algerian sahara

    African Journals Online (AJOL)

    I. Larkem

    2017-09-01

    Sep 1, 2017 ... doi: http://dx.doi.org/10.4314/jfas.v9i3. Journal of Fundamental and Applied Scienc ... a better qualitative and quantitative analysis of the species iden cal indices were used. ned was .... The important presence of these orders in our traps may be due to the characteristics of our flowering plant that promotes ...

  17. First Algerian research reactor

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    In 1985, both the Algerian Commissariat of New Energies and the Argentine National Atomic Energy Commission plus the firm INVAP S.E., started a series of mutual visits aimed at defining the mechanisms for cooperation in the nuclear field. Within this framework, a commercial contract was undersigned covering the supply of a low-power reactor (RUN), designed for basic and applied research in the fields of reactor physics and nuclear engineering. The reactor may also be used for performing experiences with neutron beams, for the irradiation of several materials and for the training of technicians, scientists and operators [es

  18. An Algerian Minister visits CERN

    CERN Multimedia

    2006-01-01

    The Algerian Minister of Higher Education and Scientific Research, Rachid Haraoubia, visited CERN on 14 November. His party included the Rector of the University of Blida and the Director of the Algerian Ecole Nationale Polytechnique. Welcomed by CERN's Director-General, Robert Aymar, and Secretary-General, Maximilien Metzger, he signed the VIP Visitors' Book before going on to visit the ATLAS experiment and the LHC tunnel. He then had the opportunity to meet Algerian scientists working at CERN. Some fifteen Algerian physicists attached to European and US institutes are participating in the LHC experiments, in particular ATLAS. A formal collaboration agreement between Algeria and CERN is expected to be drawn up in the near future.

  19. Hibiscus acetosella 'Sahara Sunset'

    Science.gov (United States)

    The Agricultural Research Service, United States Department of Agriculture, hereby release to nurserymen a new African Hibiscus, Hibiscus acetosella Welw. ex Hiern., named ‘Sahara Sunset’. This cultivar, tested as HAC06-11 was selected from a group seedlings grown at the Thad Cochran Southern Horti...

  20. Afrika bezuiden de Sahara

    NARCIS (Netherlands)

    Abbink, G.J.; Driessen, H.

    1997-01-01

    In Afrika bezuiden de Sahara heeft de islam een bijzonder complexe en rijke geschiedenis. De auteur schetst deze geschiedenis vanaf 615, wanneer de Profeet een groot deel van zijn volgelingen naar Ethiopi‰ stuurt, tot de hedendaagse periode van mondialisering, waarin de islam zich manifesteert als

  1. Sahara en mouvement

    OpenAIRE

    Casajus, Dominique

    2013-01-01

    On peut dire du Sahara ce que Fernand Braudel disait naguère de la Méditerranée : lui assigner des bornages est une tâche malaisée. Des géographes s’y sont cependant essayés, et leurs tentatives participent de ce qu’on peut appeler l’« invention » du Sahara. La présente introduction évoque quelques figures marquantes de cette invention (Léon l’Africain, Eugène Daumas, Émile Carette, Henri Duveyrier, Robert Capot-Rey…) puis présente brièvement les diverses contributions du dossier, en les repl...

  2. Diversity of Algerian oases date palm (Phoenix dactylifera L., Arecaceae: Heterozygote excess and cryptic structure suggest farmer management had a major impact on diversity.

    Directory of Open Access Journals (Sweden)

    Souhila Moussouni

    Full Text Available Date palm (Phoenix dactyliferaL. is the mainstay of oasis agriculture in the Saharan region. It is cultivated in a large part of the Mediterranean coastal area of the Sahara and in most isolated oases in the Algerian desert. We sampled 10 oases in Algeria to understand the structure of date palm diversity from the coastal area to a very isolated desert location. We used 18 microsatellite markers and a chloroplast minisatellite to characterize 414 individual palm trees corresponding to 114 named varieties. We found a significant negative inbreeding coefficient, suggesting active farmer selection for heterozygous individuals. Three distinct genetic clusters were identified, a ubiquitous set of varieties found across the different oases, and two clusters, one of which was specific to the northern area, and the other to the drier southern area of the Algerian Sahara. The ubiquitous cluster presented very striking chloroplast diversity, signing the frequency of haplotypes found in Saudi Arabia, the most eastern part of the date palm range. Exchanges of Middle Eastern and Algerian date palms are known to have occurred and could have led to the introduction of this particular chlorotype. However, Algerian nuclear diversity was not of eastern origin. Our study strongly suggests that the peculiar chloroplastic diversity of date palm is maintained by farmers and could originate from date palms introduced from the Middle East a long time ago, which since then, hasbeen strongly introgressed. This study illustrates the complex structure of date palm diversity in Algerian oases and the role of farmers in shaping such cryptic diversity.

  3. Diversity of Algerian oases date palm (Phoenix dactylifera L., Arecaceae): Heterozygote excess and cryptic structure suggest farmer management had a major impact on diversity.

    Science.gov (United States)

    Moussouni, Souhila; Pintaud, Jean-Christophe; Vigouroux, Yves; Bouguedoura, Nadia

    2017-01-01

    Date palm (Phoenix dactyliferaL.) is the mainstay of oasis agriculture in the Saharan region. It is cultivated in a large part of the Mediterranean coastal area of the Sahara and in most isolated oases in the Algerian desert. We sampled 10 oases in Algeria to understand the structure of date palm diversity from the coastal area to a very isolated desert location. We used 18 microsatellite markers and a chloroplast minisatellite to characterize 414 individual palm trees corresponding to 114 named varieties. We found a significant negative inbreeding coefficient, suggesting active farmer selection for heterozygous individuals. Three distinct genetic clusters were identified, a ubiquitous set of varieties found across the different oases, and two clusters, one of which was specific to the northern area, and the other to the drier southern area of the Algerian Sahara. The ubiquitous cluster presented very striking chloroplast diversity, signing the frequency of haplotypes found in Saudi Arabia, the most eastern part of the date palm range. Exchanges of Middle Eastern and Algerian date palms are known to have occurred and could have led to the introduction of this particular chlorotype. However, Algerian nuclear diversity was not of eastern origin. Our study strongly suggests that the peculiar chloroplastic diversity of date palm is maintained by farmers and could originate from date palms introduced from the Middle East a long time ago, which since then, hasbeen strongly introgressed. This study illustrates the complex structure of date palm diversity in Algerian oases and the role of farmers in shaping such cryptic diversity.

  4. Sahara: Barrier or corridor? Nonmetric cranial traits and biological affinities of North African late Holocene populations.

    Science.gov (United States)

    Nikita, Efthymia; Mattingly, David; Lahr, Marta Mirazón

    2012-02-01

    The Garamantes flourished in southwestern Libya, in the core of the Sahara Desert ~3,000 years ago and largely controlled trans-Saharan trade. Their biological affinities to other North African populations, including the Egyptian, Algerian, Tunisian and Sudanese, roughly contemporary to them, are examined by means of cranial nonmetric traits using the Mean Measure of Divergence and Mahalanobis D(2) distance. The aim is to shed light on the extent to which the Sahara Desert inhibited extensive population movements and gene flow. Our results show that the Garamantes possess distant affinities to their neighbors. This relationship may be due to the Central Sahara forming a barrier among groups, despite the archaeological evidence for extended networks of contact. The role of the Sahara as a barrier is further corroborated by the significant correlation between the Mahalanobis D(2) distance and geographic distance between the Garamantes and the other populations under study. In contrast, no clear pattern was observed when all North African populations were examined, indicating that there was no uniform gene flow in the region. Copyright © 2011 Wiley Periodicals, Inc.

  5. Sahara Dust Cloud

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Dust Particles Click on the image for Quicktime movie from 7/15-7/24 A continent-sized cloud of hot air and dust originating from the Sahara Desert crossed the Atlantic Ocean and headed towards Florida and the Caribbean. A Saharan Air Layer, or SAL, forms when dry air and dust rise from Africa's west coast and ride the trade winds above the Atlantic Ocean. These dust clouds are not uncommon, especially during the months of July and August. They start when weather patterns called tropical waves pick up dust from the desert in North Africa, carry it a couple of miles into the atmosphere and drift westward. In a sequence of images created by data acquired by the Earth-orbiting Atmospheric Infrared Sounder ranging from July 15 through July 24, we see the distribution of the cloud in the atmosphere as it swirls off of Africa and heads across the ocean to the west. Using the unique silicate spectral signatures of dust in the thermal infrared, AIRS can detect the presence of dust in the atmosphere day or night. This detection works best if there are no clouds present on top of the dust; when clouds are present, they can interfere with the signal, making it much harder to detect dust as in the case of July 24, 2005. In the Quicktime movie, the scale at the bottom of the images shows +1 for dust definitely detected, and ranges down to -1 for no dust detected. The plots are averaged over a number of AIRS observations falling within grid boxes, and so it is possible to obtain fractional numbers. [figure removed for brevity, see original site] Total Water Vapor in the Atmosphere Around the Dust Cloud Click on the image for Quicktime movie The dust cloud is contained within a dry adiabatic layer which originates over the Sahara Desert. This Saharan Air Layer (SAL) advances Westward over the Atlantic Ocean, overriding the cool, moist air nearer the surface. This burst of very dry air is visible in the AIRS retrieved total water

  6. Secret story of the Algerian oil

    International Nuclear Information System (INIS)

    Malti, H.

    2010-01-01

    This book unravels some obscure aspects of oil exploitation in Algeria, from its historical aspects (the first discoveries, the collaboration with French oil companies during the 1960's, the nationalization in 1971) to the drift of the Algerian regime towards corruption and conflicts between the power clans with the connivance of big democracies

  7. SYNTHESIS OF MCM-41 NANOMATERIAL FROM ALGERIAN ...

    African Journals Online (AJOL)

    T. Ali-Dahmane

    1 mai 2017 ... Journal of Fundamental and Applied Sciences is licensed under a Creative Commons Attribution-NonCommercial 4.0. International License. Libraries Resource Directory. We are listed under Research Associations category. SYNTHESIS OF MCM-41 NANOMATERIAL FROM ALGERIAN BENTONITE:.

  8. Physicochemical parameters and antibiotics residuals in Algerian ...

    African Journals Online (AJOL)

    The physicochemical analyses of the Algerian honeys show that 56% of samples correspond to Codex standards and 44% not in conformity with the standards required by the Codex Alimentarius and EU, because part of the samples had one or more defects. The percentage not in conformity was due to the high rates of ...

  9. Estructura de la población prehistórica del noroeste argentino (sector septentrional

    Directory of Open Access Journals (Sweden)

    Varela, Héctor Hugo

    2004-01-01

    Full Text Available Se estudió la estructura de la poblaci6n prehistórica del sector septentrional del noroeste argentino mediante el empleo de caracteres no-métricos del cráneo. La muestra está constituida por 673 individuos pertenecientes a las regiones de Puna (111, Quebrada de Humahuaca (269, Selvas Occidentales (50 y Valliserrana (243. Se observaron 33 caracteres y se aplicó un diseño tipo factorial "i" por "j" para tablas de contingencia. Mediante la prueba X2 se analizó la distribuci6n de la muestra por sexo, edad, deformación artificial y región. La estructura de la población se estudió empleando análisis de correspondencia, medida media de divergencia estandarizada (sMMD y análisis de agrupamiento. Se comprobó que seis rasgos están asociados con deformación, cinco con sexo, siete con edad y doce con región. Los resultados multivariados revelaron la existencia de dos componentes biológicos, uno constituido por Quebrada de Humahuaca y la Puna y otro por Valliserrana y Las Pirguas. Es posible que dichos componentes se hayan originado a partir de un mismo grupo ancestral probablemente de origen andino y que luego se diferenciaron por la acción de diferentes factores evolutivos (pautas particulares de apareamiento, deriva y migración.

  10. Africa (south of the Sahara)

    NARCIS (Netherlands)

    Hoorweg, J.C.; Sexton, V.S.; Msiak, H.

    1976-01-01

    This review of the development and current status of psychology in Africa focuses on Africa south of the Sahara, excluding South Africa. The author discusses the research topics which have attracted the attention of psychologists in Africa, including perception (illusions, pictorial representation

  11. Electrofacies classification using the self-organizing map approach with an example from the Algerian Sahara

    Science.gov (United States)

    Sokhal, Abdallah; Benaissa, Zahia; Ouadfeul, Sid Ali; Boudella, Amar

    2017-04-01

    The characterization of electrofacies is essential for reservoir modeling. However, this is a process that depends on many variables, with errors and associated noise that interfere on visual interpretation. In this paper, we propose an approach to characterize the reservoir properties of the Quartzite of Hamra formation. This method integrates geological and petrophysical data and compares them with the field performance analysis to achieve a practical electrofacies clustering. The petrophysical data used are from Hassi Guettar field in Hassi Messaoud basin. The neutron porosity, gamma ray and density profiles were studied to classify the field's reservoir lithology. An unsupervised neural network was employed based on the self-organizing map (SOM) technique to identify and extract electrofacies groups. Based on the results of the SOM method, the target reservoir is classified into five electrofacies clusters (EF1-EF5) among which the EF1, EF2 and EF3 show the best reservoir quality. The EF4 indicates moderate reservoir quality, while the EF5 shows no reservoir quality. Key words: Neural networks - Self-organizing map - Electrofacies - Porosity - Gamma ray - Density.

  12. Chemical composition, antioxidant and antibacterial properties of Pteranthus dichotomus from Algerian Sahara.

    Science.gov (United States)

    Allaoua, Zina; Benkhaled, Mohammed; Dibi, Ammar; Long, Christophe; Aberkane, Mohammed Cherif; Bouzidi, Soumia; Kassah-Laouar, Ahmed; Haba, Hamada

    2016-01-01

    The phytochemical study of ethyl acetate and n-butanol extracts of Pteranthus dichotomus Forssk. led to the isolation and identification of 11 compounds, including three glycolipids 1-3, one lignan 4, three flavonoids 5-7 and four phytosterols 8-11. Structures of the isolated compounds have been elucidated by analysis of 1D and 2D NMR data, and mass spectrometry EI-MS and ESI-MS and by comparison with literature data. Furthermore, the ethyl acetate and n-butanol extracts were examined for their antioxidant and antibacterial activities. The results showed that both extracts (PDAC and PDBU) had a moderate antioxidant activity (IC50 = 375.514 μg/mL and 691.333 μg/mL) respectively.

  13. Evaluation of the Algerian photovoltaic market potential

    International Nuclear Information System (INIS)

    Labed, S.; Lorenzo, E.

    2003-01-01

    The Algerian energy sector will certainly face a crisis this century with the gradual diminution of oil and gas reserves estimated at 4.2 billion Toe (Tons of oil equivalent), which can last for only a few decades at today's production levels. In the meantime the population and its energy needs will have doubled. This situation is complicated by the fact that the energy sector is Algeria's major source of revenue, and finances the national economy at a level of 66%. Many decision-makers now agree that time has come to implement a new energy policy, based on energy diversification, and to set up new mechanisms. The Algerian energy sector is still dominated by hydrocarbons, and has promoted a major effort to reach a mean national electrification rate of 96%. Nevertheless, the remaining zones are very isolated and widespread. The conventional electrification solutions or grid extensions are no longer economically viable. The recourse to renewable energies in general and PV solar energy in particular has become a reality. This source represents a good alternative for 85% of Algerian territory, which is composed of arid and semi-arid zones, characterized by low population density and limited energy needs. These regions represent a strategic alternative in order to reverse the population migration and to encourage a new migration to the south, since northern Algeria is less and less welcoming (high population density, unemployment, shrinkage of agricultural land, inflation). In this paper we try to evaluate the potential of the Algerian PV market in order to inform decision-makers and future investors. To this end, and after identifying the PV solar energy segments, we attempt to estimate them under different scenarios. (Author)

  14. South of Sahara | Page 306 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. flexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. Read more about Afrique subsaharienne ...

  15. Language and conflict : Kabylia and the Algerian state

    OpenAIRE

    Mouhleb, Naima

    2005-01-01

    In April 2001, the Berber region of Kabylia exploded in a series of violent riots that led to the death of 123 civilians and the withdrawal of all the Algerian Gendarmerie forces from the region. Algerian society seemed on the verge of a new destabilizing conflict only shortly after the disarmament of the majority of the armed Islamist groups. The riots spread to Eastern and Western Algerian cities in June 2001. What initially was viewed as an ethnic uprising suddenly took on a socio-politica...

  16. Representing the Algerian Civil War: Literature, History, and the State

    OpenAIRE

    Landers, Neil Grant

    2013-01-01

    "Representing the Algerian Civil War: Literature, History, and the State" addresses the way the Algerian civil war has been portrayed in 1990s novelistic literature. In the words of one literary critic, "The Algerian war has been, in a sense, one big murder mystery." This may be true, but literary accounts portray the "mystery" of the civil war--and propose to solve it--in sharply divergent ways. The primary aim of this study is to examine how three of the most celebrated 1990s novels depict...

  17. Cretaceous Crocodyliforms from the Sahara

    Directory of Open Access Journals (Sweden)

    Paul Sereno

    2009-11-01

    Full Text Available Diverse crocodyliforms have been discovered in recent years in Cretaceous rocks on southern landmasses formerly composing Gondwana.  We report here on six species from the Sahara with an array of trophic adaptations that significantly deepen our current understanding of African crocodyliform diversity during the Cretaceous period.  We describe two of these species (Anatosuchus minor, Araripesuchus wegeneri from nearly complete skulls and partial articulated skeletons from the Lower Cretaceous Elrhaz Formation (Aptian-Albian of Niger. The remaining four species (Araripesuchus rattoides sp. n., Kaprosuchus saharicus gen. n. sp. n., Laganosuchus thaumastos gen. n. sp. n., Laganosuchus maghrebensis gen. n. sp. n. come from contemporaneous Upper Cretaceous formations (Cenomanian in Niger and Morocco.

  18. Performance of Algerian SME: evaluation by the FDH approach

    Directory of Open Access Journals (Sweden)

    Ali Nabil BELOUARD

    2014-06-01

    Full Text Available This paper aims to apply the nonparametric frontier analysis to evaluate the performance of the Algerian private SMS. The interest of a good measure of firm performance is to have a good reference (benchmark. For that, it seems important and useful to present an appropriate approach to construct the Benchmarking, and to illustrate it through an application upon a sample of Algerian SMS’s in order to evaluate suitably their performance.

  19. Melissopalynological Characterization of North Algerian Honeys

    Directory of Open Access Journals (Sweden)

    Samira Nair

    2013-03-01

    Full Text Available A pollen analysis of Algerian honey was conducted on a total of 10 honey samples. The samples were prepared using the methodology described by Louveaux et al., that was then further adapted by Ohe et al. The samples were subsequently observed using light microscopy. A total of 36 pollen taxa were discovered and could be identified in the analyzed honey samples. Seventy percent of the studied samples belonged to the group ofmonofloral honeys represented by Eucalyptus globulus, Thymus vulgaris, Citrus sp. and Lavandula angustifolia. Multifloral honeys comprised 30% of the honey samples, with pollen grains of Lavandula stoechas (28.49% standing out as the most prevalent. Based on cluster analysis, two different groups of honey were observed according to different pollen types found in the samples. The identified pollen spectrum of honey confirmed their botanical origin.

  20. 5th Algerian Congress of Mechanics

    CERN Document Server

    Pluvinage, Guy; Azouaoui, Krimo

    2017-01-01

    This book covers a variety of topics in mechanics, with a special emphasis on material mechanics. It reports on fracture mechanics, fatigue of materials, stress-strain behaviours, as well as transferability problems and constraint effects in fracture mechanics. It covers different kind of materials, from metallic materials such as ferritic and austenitic steels, to composites, concrete, polymers and nanomaterials. Additional topics include heat transfer, quality control and reliability of structures and components. Furthermore, the book gives particular attention to new welding technologies such as STIR welding and spray metal coating, and to novel methods for quality control, such as Taguchi design, fault diagnosis and wavelet analysis. Based on the 2015 edition of the Algerian Congress of Mechanics (Congrès Algérien de Mécanique, CAM), the book also covers energetics, in terms of simulation of turbulent reactive flow, behaviour of supersonic jet, turbulent combustion, fire induced smoke layer, and heat a...

  1. Cenozoic stratigraphy of the Sahara, Northern Africa

    Science.gov (United States)

    Swezey, Christopher S.

    2009-01-01

    This paper presents an overview of the Cenozoic stratigraphic record in the Sahara, and shows that the strata display some remarkably similar characteristics across much of the region. In fact, some lithologies of certain ages are exceptionally widespread and persistent, and many of the changes from one lithology to another appear to have been relatively synchronous across the Sahara. The general stratigraphic succession is that of a transition from early Cenozoic carbonate strata to late Cenozoic siliciclastic strata. This transition in lithology coincides with a long-term eustatic fall in sea level since the middle Cretaceous and with a global climate transition from a Late Cretaceous–Early Eocene “warm mode” to a Late Eocene–Quaternary “cool mode”. Much of the shorter-term stratigraphic variability in the Sahara (and even the regional unconformities) also can be correlated with specific changes in sea level, climate, and tectonic activity during the Cenozoic. Specifically, Paleocene and Eocene carbonate strata and phosphate are suggestive of a warm and humid climate, whereas latest Eocene evaporitic strata (and an end-Eocene regional unconformity) are correlated with a eustatic fall in sea level, the build-up of ice in Antarctica, and the appearance of relatively arid climates in the Sahara. The absence of Oligocene strata throughout much of the Sahara is attributed to the effects of generally low eustatic sea level during the Oligocene and tectonic uplift in certain areas during the Late Eocene and Oligocene. Miocene sandstone and conglomerate are attributed to the effects of continued tectonic uplift around the Sahara, generally low eustatic sea level, and enough rainfall to support the development of extensive fluvial systems. Middle–Upper Miocene carbonate strata accumulated in northern Libya in response to a eustatic rise in sea level, whereas Upper Miocene mudstone accumulated along the south side of the Atlas Mountains because uplift of the

  2. Accumulated Testimony: Layering French Girls’ Diaries on the Algerian Exodus

    OpenAIRE

    Amy L Hubbell

    2014-01-01

    In 1997, French-Algerian author Leïla Sebbar published an illustrated children’s book, J’étais enfant en Algérie, juin 1962 (‘I was a child in Algeria, June 1962’) in which she creates the fictional account of a young girl from the interior of Algeria leaving her home during the great exodus of the French just prior to Algerian independence. Using the genre of diary writing, Sebbar’s text reads as testimonial of fleeing their country for a homeland they do not know. Although this text is ...

  3. Eghindi among Sahrawi refugees of Western Sahara

    NARCIS (Netherlands)

    Volpato, G.

    2014-01-01

    Eghindi is an illness built around a set of pathological states experienced by Sahrawi in the desert environment of Western Sahara. Its core symptoms are caused by osmotic imbalances related to salt consumption. In 1975, many Sahrawi were exiled into refugee camps, and they have since experienced

  4. JPRS Report Africa (Sub-Sahara)

    Science.gov (United States)

    1987-09-16

    16 SEPTEMBER 1987 AFRICA (SUB-SAHARA) CONTENTS INTER-AFRICAN GHANA U.S.-Conceived Debt Plans Said Not To Work for Africa (Jan Toporowski ...TO WORK FOR AFRICA London AFRICA ANALYSIS in English 10 Jul 87 p 4 [Article by Jan Toporowski ] lText] THE last edition of Africa Analysis

  5. Are the Complex Algerian Meteoritic Craters Potential Hydrocarbon Traps?

    Science.gov (United States)

    Belhai, D.; Merle, O.; Vincent, P.; Afalfiz, A.; Devouard, B.

    2005-03-01

    The geological analysis of the meteoritic craters of Tin Bider and Ouarkziz (Sahara, Algeria) reveals identical characters to those of Ava and Viewfield. Their detailed study will make it possible to slice as for the presence or not ofhydrocarbons.

  6. Chemical composition and digestibility of some browse plant species collected from Algerian arid rangelands

    Energy Technology Data Exchange (ETDEWEB)

    Boufennara, S.; Lopez, S.; Boussebouna, H.; Bodas, R.; Bouazza, L.

    2012-11-01

    Many wild browse and bush species are undervalued mainly because of insufficient knowledge about their potential feeding value. The objective was to evaluate some nutritional attributes of various Algerian browse and shub species (Atriplex halimus, Artemisia campestris, Artemisia herba-alba, Astragalus gombiformis, Calobota saharae, Retama raetam, Stipagrostis pungens, Lygeum spartum and Stipa tenacissima). Chemical composition, phenols and tannins concentration, in vitro digestibility, in vitro gas production kinetics and in vitro bio-assay for assessment of tannins using buffered rumen fluid, and in situ disappearence of the edible parts of the plants (leaves, thin twigs and flowers) were determined. In general, protein content in dicotyledon species was always greater than in monocotyledon grasses, these showing higher neutral and acid detergent fibre and lower lignin contents than dicots. The tannin concentrations varied considerably between species, but in general the plants investigated in this study had low tannin contents (except for Artemisia spp. and S. tenacissima). Monocots showed lower in vitro and in situ digestibilities, fermentation rate, cumulative gas production and extent of degradation than dicot species. The plants were clustered by principal components analysis in two groups: poor-quality grasses and the most digestible dicot species. Chemical composition (neutral detergent fibre and protein) and digestibility were the main influential variables determining the ranking. In conclusion, A. halimus, A. campestris, A. herba-alba and A. gombiformis can be considered of greater nutritional value than the highly fibrous and low digestible grasses (S. pungens, L. spartum and S. tenacissima) that should be considered emergency roughages. (Author) 46 refs.

  7. Sero-epidemiology of bluetongue in Algerian ruminants

    African Journals Online (AJOL)

    BMH Labo SPA

    2016-05-18

    May 18, 2016 ... the herds and lack of Culicoides controls strategies were the major risk factors for bluetongue sero- positivity in Algerian ruminant ... coastline at the Mediterranean Sea; most of the coastal area. (northern region) is hilly, .... Culicoides control measures in disease prevention strategy may play a key role in ...

  8. Characterization of lactic acid bacteria isolated from Algerian arid ...

    African Journals Online (AJOL)

    Diversity and density of lactic acid bacteria isolated from Algerian raw goats\\' milk in arid zones were studied by determination of morphological, cultural, physiological and biochemical characteristics. 206 lactic acid bacterial strains were isolated, with 115 of them belonging to lactic acid cocci and others to the genus, ...

  9. Antifungal activity of methanolic extracts of four Algerian marine ...

    African Journals Online (AJOL)

    The highest inhibiting effect was noted for Rhodomela confervoides (red algae) and Padina pavonica (brown algae), respectively against Candida albicans ... These results suggest that seaweeds collected from Algerian coast present a significant capacity which makes them interesting for screening for natural products.

  10. Synthesis of MCM-41 nanomaterial from Algerian bentonite ...

    African Journals Online (AJOL)

    Mesoporous materials of the MCM-41 type were synthesized from Algerian bentonite as an aluminosilicate source without the addition of pure silica and aluminum reagents. The samples were synthesized under hydrothermal condition using cetyltrimithylammonium bromide (CTAB) as surfactant. The influence of initial ...

  11. A study of sounds produced by Algerian esophageal speakers ...

    African Journals Online (AJOL)

    Background: Total Laryngectomy is a mode of treatment of patients with advanced laryngeal cancer. It affects the voice and the speech communication. Objective: To present an acoustic analysis of the new voice after total laryngectomy in Algerian hospital environment. Methods: A corpus of sounds was collected from ...

  12. Molecular genetic study of hemophilia B in an Algerian population ...

    African Journals Online (AJOL)

    exogenous factor XI) development is currently the most significant treatment complication. In this study, we evaluated the relationship between inhibitor development and FIX gene mutation types. In summary, our preliminary results will be used to build an Algerian mutation database which would facilitate genetic counseling ...

  13. Results of prostatic biopsies in Algerian patients with an elevated ...

    African Journals Online (AJOL)

    Objective: to report on prostatic biopsy results in Algerian patients presenting with a suspicious Digital Rectal Examination (DRE) and\\or an elevated total PSA. Methods: data collected on prepared index cards were age, result of DRE, rate of PSA and number of cores, as well as the histological result. The biopsies were ...

  14. Molecular genetic study of hemophilia B in an Algerian population

    African Journals Online (AJOL)

    DELL

    2016-12-21

    Dec 21, 2016 ... genetic predisposition of developing inhibitors. The objective of this study were, to identify the mutations that produce different forms of HB disease among Algerian patients, to characterise mutations of the. FIX gene and to develop our knowledge about the molecular basis of this disease. MATERIALS AND ...

  15. The determinants of financial structure in the algerian enterprises: A ...

    African Journals Online (AJOL)

    The results of our research indicate that the Algerian SMEs and large companies have almost the same determinants of financial structure, i.e. the debt rate, the rate of sustainable growth and profitability. The undercapitalization of SMEs has negative repercussions on their financial structure and, consequently, on their ...

  16. Geochronological data on the Amsinassene-Tefedest Block (Central Hoggar, Algerian Sahara) and evidence for its polycyclic evolution

    International Nuclear Information System (INIS)

    Vialette, Y.; Vitel, G.

    1979-01-01

    The history of the Amsinassene-Tefedest Block, in the central Hoggar domain, is characterized by a polycyclic evolution. The unreliable 1970 Ma age obtained on the Arechchoum gneisses, known to be Suggarian-Eburnean, might represent the effect of the Eburnean orogeny. A Rb/Sr whole-rock age on the leucocratic fractions of gneisses point to a kibaran migmatization. This age confirms the existence of a Kibaran orogeny shown in the Aleksod area. The Pharusian-Pan African cycle, in this domain, is characterized by the emplacement of huge granitic bodies during two distinct magnetic phases: one of Late Proterozoic age (670 Ma) or Imezzarian phase, the other of Cambrian age as shown by the 546 and 515 Ma Rb/Sr whole-rock ages obtained on late kinematic granitic plutons, Iskelian phase. The younger mineral ages (470-430 Ma) indicate late vertical uplift of the central Hoggar. (Auth.)

  17. Chemical constituents of essential oil of endemic Rhanterium suaveolens Desf. growing in Algerian Sahara with antibiofilm, antioxidant and anticholinesterase activities.

    Science.gov (United States)

    Chemsa, Ahmed Elkhalifa; Erol, Ebru; Öztürk, Mehmet; Zellagui, Amar; Özgür, Ceylan; Gherraf, Noureddine; Duru, Mehmet Emin

    2016-09-01

    Twenty compounds were detected in the essential oil of Rhanterium suaveolens representing 98.01% of the total oil content. Perillaldehyde (45.79%), caryophyllene oxide (24.82%) and β-cadinol (5.61%) were identified as the main constituents. In β-carotene-linoleic acid assay, both the oil and the methanol extract exhibited good lipid peroxidation inhibition activity, with IC50 values of 17.97 ± 5.40 and 11.55 ± 3.39 μg/mL, respectively. In DPPH and CUPRAC assays, however, the methanol extract exhibited a good antioxidant activity. The highest antibiofilm activity has been found 50.30% against Staphylococcus epidermidis (MU 30) at 20 μg/mL for essential oil and 58.34% against Micrococcus luteus (NRRL B-4375) at 25 mg/mL concentration for methanol extract. The in vitro anticholinesterase activity of methanol extract showed a moderate acetylcholinesterase inhibitory (IC50 = 168.76 ± 0.62 μg/mL) and good butyrylcholinesterase inhibitory (IC50 = 54.79 ± 1.89 μg/mL) activities. The essential oil was inactive against both enzymes.

  18. Lithosphere Structure of the Rivera Plate - Jalisco Block Contact Zone: Septentrional Region of the Islas Marías (Mexico)

    Science.gov (United States)

    Madrigal-Ávalos, L. A.; Nunez, D.; Escalona-Alcazar, F. D. J.; Nuñez-Cornu, F. J.; Barba, D. C., Sr.; Danobeitia, J.

    2017-12-01

    The western margin of Mexico is a tectonic complex region where large earthquakes occurred with very destructive consequences, including the generation of big tsunamis. This fact is mainly the result of the Rivera plate subduction beneath the North American plate and the Jalisco Block implying a high potential seismic risk. In the north, between the Tamayo Fracture Zone and the Mesoamerican Trench, the Islas Marías region is a complex tectonic limit within the interaction of the Rivera plate oceanic crust and the Jalisco Block continental crust. In order to know the shallow and deep structure of the Rivera plate - Jalisco Block contact zone and to be able to determine these potential seismic sources, the TSUJAL geophysical experiment was carried out from 2012 to 2016. As part of this project, we present the results of the processed and analyzed MCS and WAS data along the TS09 and RTSIM01 seismic transects, respectively, across the septentrional region of Islas Marías. These marine seismic lines are coincident with 110 km length for MCS and 240 km for WAS, and perpendicular to the coastline with SW-NE orientation. The seismic sources used in this work aboard RRS James Cook consisted of 12 guns with a total capacity for WAS data of 5800 in3 every 120 s and 3540 in3 every 50 m for MCS data. The MCS data were acquired with a 5.85 km length streamer with a 468 active channels, while the WAS data were recorded by a network of 4 OBS and 27 land seismic stations. After data processing and joint interpretation, it was possible to determine that shallow structure is mainly constituted by normal faults associated to graben structures forming sedimentary basins with non-deformed sediments in the basement. While the deep structure is characterized by depths from 9 to 12 km in the oceanic crust and 18 to 21 km in the continental crust. The deepest layers of the upper mantle were determined up to 35 km depth. In this study, it was possible to calculate a dip angle between 6

  19. Daytime passerine migrants over the Sahara — are these diurnal ...

    African Journals Online (AJOL)

    When crossing the Sahara it was expected that nocturnal migrants would continue their flight into the day. We investigated whether migration taking place in the Sahara during daytime comprises the normal diurnal migrant species or the nocturnal ones prolonging their flight into the day. Birds departing from the Sahel in ...

  20. South of Sahara | Page 54 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Building a Community ICT Network in Mozambique. Language English. Read more about Appui au réseautage et au renforcement des télécentres communautaires au Mali. Language French. Read more about Support for Community Telecentres and Networks in Mali.

  1. South of Sahara | Page 18 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Changements climatiques et santé des autochtones. Language French. Read more about Strengthening Equity through Applied Research Capacity Building in e-Health. Language English. Read more about La législation sur le salaire minimum, son application et la ...

  2. South of Sahara | Page 99 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Institutional Support : Makerere Institute of Social Research (MISR). Language English. Read more about Soutien institutionnel au Makerere Institute of Social Research (MISR). Language French. Read more about Soutien institutionnel à l'Institute for Economic Affairs ...

  3. South of Sahara | Page 49 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Soutien institutionnel au Nigerian Institute of Social and Economic Research (NISER). Language French. Read more about Institutional Support : Nigerian Institute of Social and Economic Research (NISER). Language English. Read more about Institutional Support ...

  4. South of Sahara | Page 38 | IDRC - International Development ...

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    South of Sahara. Sud du Sahara. Read more about Integrated Intervention for Diabetes Risk After Gestational Diabetes in South Africa. Language English. Read more about Essais cliniques d'un vaccin expérimental contre le virus Ebola : une intervention canadienne dans la recherche. Language French. Read more about ...

  5. South of Sahara | Page 33 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Recherche sur les ressources éducatives libres au service du développement. Language French. Read more about Research into Open Educational Resources for Development. Language English. Read more about Recours au droit administratif pour renforcer la ...

  6. South of Sahara | Page 38 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Interaction entre zones urbaines et rurales et changements climatiques (Nigeria). Language French. Read more about Compliance with Private Food Safety Standards among Smallholders in Kenya. Language English. Read more about Respect des normes de salubrité ...

  7. South of Sahara | Page 129 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Fonds de recherche sur le climat d'affaires et d'investissement. Language French. Read more about Investment Climate and Business Environment Research Fund. Language English. Read more about Villes ciblées - recyclage des déchets et négoce agricole à Kampala, ...

  8. South of Sahara | Page 135 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Incubateur de petites et microentreprises de technologie (MICTI) - phase III. Language French. Read more about Mozambique Information and Communication Technology : Micro and Small Enterprises Incubator - Phase III. Language English. Read more about Utilisation ...

  9. South of Sahara | Page 49 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Livelihood Diversification for Smallholder Tobacco Farmers in South Nyanza, Kenya - Phase I. Language English. Read more about Initiative de renforcement des capacités de recherche en santé au Kenya et au Malawi - phase de démarrage. Language French.

  10. South of Sahara | Page 112 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Implementation of an Electronic Strategy in Bénin. Language English. Read more about E-Stratégie du Bénin : programme de recherches multidisciplinaires d'appui à sa mise en oeuvre. Language French. Read more about Libéralisation du commerce des biens et ...

  11. South of Sahara | Page 102 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Partnership for adapting Vulnerable Populations to Soil Salinization resulting from Climate Change in Sénégal. Language English. Read more about Partenariat pour l'adaptation des populations vulnérables à la salinization des sols induite par les changements ...

  12. South of Sahara | Page 80 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Empowering Developing Countries on the UN Security Council. Language English. Read more about Civil Society and Public Powers : Partners for Social Economy and Solidarity. Language English. Read more about Société civile et pouvoirs publics : Partenaires pour ...

  13. South of Sahara | Page 13 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Promoting inclusive policies and approaches to address youth networks of violence in South Africa. Language English. Read more about Nanostructures for the development of vaccines against avian influenza virus. Language English. Read more about Deepening ...

  14. South of Sahara | Page 129 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Contribution of ICTs to the Rejection of Female Genital Mutilation in Francophone West Africa. Language English. Read more about Contribution des TICs à l'abandon des mutilations génitales féminines en Afrique de l'Ouest francophone. Language French. Read more ...

  15. South of Sahara | Page 14 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Renforcement des connaissances économiques et de la capacité d'adaptation face aux changements climatiques au Bénin. Language French. Read more about Strengthening Economic Skills and Climate Change Adaptive Capacity in Bénin. Language English.

  16. South of Sahara | Page 33 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Hybrid Security Arrangements in Africa: Exploring the Implications for State-building. Language English. Read more about Chiffrer le travail des femmes - économie sexiste sur le marché et au foyer. Language French. Read more about Implications des mécanismes de ...

  17. South of Sahara | Page 133 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Cigarette Taxation in Tanzania. Language English. Read more about Vers une structure de sécurité régionale dans la Corne de l'Afrique - phase II. Language French. Read more about Toward a Regional Security Architecture for the Horn of Africa - Phase II. Language ...

  18. South of Sahara | Page 12 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Young Women's Political Participation in Malawi. Language English. Read more about Apprentissage, transparence et création de liens : femmes parlementaires et jeunes étudiantes universitaires en Éthiopie. Language French. Read more about Learning, Transparency ...

  19. South of Sahara | Page 34 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Women's Access to Land and Natural Resources in Pastoralist and Forest Communities in East Africa. Language English. Read more about Pratiques foncières et droit des femmes à la terre : répercussions sur l'accès aux ressources naturelles (Cameroun anglophone).

  20. South of Sahara | Page 41 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Rural Urban Cooperation on Water Management in the Context of Climate Change in Burkina Faso. Language English. Read more about Adaptation des politiques de pêche aux changements climatiques à l'aide des savoirs scientifiques et de connaissances endogènes ...

  1. South of Sahara | Page 13 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Participation des jeunes femmes à la vie politique en Égypte : imaginer le politique. Language French. Read more about Imagining the Political : Young Women, Participation and the Crafting of the Political in Egypt. Language English. Read more about Contribution des ...

  2. South of Sahara | Page 27 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Agriculture for Improved Nutrition and Health: Support to the Consultative Group on International Agricultural Research Program. Language English. Read more about The Role of Militia, Predatory State Authorities, and Rogue Capital in the Horn of Africa. Language ...

  3. South of Sahara | Page 78 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Gestion des milieux humides en vue d'une plus grande sécurité alimentaire en Ouganda. Language French. Read more about Moving Zimbabwe Forward : an Evidence Based Policy Dialogue. Language English. Read more about De l'avant au Zimbabwe : dialogue sur ...

  4. South of Sahara | Page 52 | IDRC - International Development ...

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    South of Sahara. Sud du Sahara. Read more about Site d'enfouissement de Mbeubeuss : à la recherche de la santé humaine, la santé environnementale et les moyens de subsistance (Sénégal). Language French. Read more about Mozambique Health Information Network. Language English. Read more about Réseau ...

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    South of Sahara. Sud du Sahara. Read more about Évaluation de l'activité entrepreneuriale dans la région MOAN. Language French. Read more about Abolition du paiement direct des services de santé en Afrique de l'Ouest. Language French. Read more about Abolition of Direct Payment for Health Services in West ...

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    South of Sahara. Sud du Sahara. Read more about Diversification des moyens de subsistance des petits producteurs de tabac du sud de la province de Nyanza, au Kenya - Phase I. Language French. Read more about Kenya-Malawi Health Research Capacity Strengthening Initiative - Inception Phase. Language English.

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    South of Sahara. Sud du Sahara. Read more about Youth Employment and Migration in West Africa. Language English. Read more about Évolution démographique asymétrique et gouvernance financière mondiale. Language French. Read more about Asymmetric Demography and Global Financial Governance.

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    South of Sahara. Sud du Sahara. Read more about La législation sur le salaire minimum, son application et la situation sur le marché du travail en Afrique du Sud, en Argentine et au Costa Rica. Language French. Read more about Mozambique Science, Technology and Innovation Review. Language English. Read more ...

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    South of Sahara. Sud du Sahara. Read more about Nouvelle constitution du Zimbabwe et campagne pour le droit à la santé de 2010. Language French. Read more about New Zimbabwe Constitution and the Right to Health Campaign 2010. Language English. Read more about Participation des jeunes femmes à la vie ...

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    South of Sahara. Sud du Sahara. Read more about Approches novatrices pour la création d'emplois pour les jeunes et leur intégration au marché du travail en Afrique de l'Est. Language French. Read more about Soutien au Programme de recherche du CGIAR sur les racines, tubercules et bananes. Language French.

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    South of Sahara. Sud du Sahara. Read more about Exemption communautaire du paiement des services de santé au Burkina Faso. Language French. Read more about Études par pays dans le cadre du HIV/AIDS Monitor. Language French. Read more about HIV/AIDS Monitor Country Studies. Language English.

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    South of Sahara. Sud du Sahara. Read more about Action multisectorielle en matière de prévention des maladies non transmissibles en Afrique subsaharienne. Language French. Read more about Safe and Inclusive Cities: Research to Reduce Urban Violence, Poverty, and Inequalities. Language English. Read more ...

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    South of Sahara. Sud du Sahara. Read more about Canada-Africa Research Exchange Grants Phase II. Language English. Read more about Subventions pour la coopération en recherche entre le Canada et l'Afrique - phase II. Language French. Read more about Mesure de l'activité entrepreneuriale en Égypte et en ...

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    South of Sahara. Sud du Sahara. Read more about Femmes, migration et droits au Mali et au Sénégal. Language French. Read more about Capacity Building in Open Medical Record System (OpenMRS) in Rwanda. Language English. Read more about Renforcement des capacités relatives à l'Open Medical Records ...

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    South of Sahara. Sud du Sahara. Read more about Suivre et contrer la circulation de l'information erronée dans le delta du fleuve Tana, au Kenya. Language French. Read more about Mapping and Countering the Flow of Misinformation in the Tana Delta of Kenya. Language English. Read more about TanZamBo Capacity ...

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    South of Sahara. Sud du Sahara. Read more about Enquête sur l'utilisation du téléphone mobile pour le développement des petites et microentreprises au Ghana. Language French. Read more about Eau, santé et adaptation aux changements climatiques en Afrique. Language French. Read more about Programme ...

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    South of Sahara. Sud du Sahara. Read more about Soutien institutionnel au Centre for the Study of the Economies of Africa (CSEA). Language French. Read more about Soutien institutionnel au Groupe de recherche en économie appliquée et théorique (GREAT) (Mali). Language French. Read more about Institutional ...

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    South of Sahara. Sud du Sahara. Read more about Approfondissement des connaissances et renforcement des capacités en matière de sexospécificités au sein du programme ACACIA. Language French. Read more about Acacia Gender Learning and Capacity Strengthening. Language English. Read more about Soutien ...

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    South of Sahara. Sud du Sahara. Read more about TTI Phase 2 Institutional Support: Advocates Coalition for Development and Environment. Language French. Read more about Soutien organisationnel de la phase 2 de l'ITT : Economic and Social Research Foundation. Language French. Read more about Structural ...

  20. South of Sahara | Page 48 | IDRC - International Development ...

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    South of Sahara. Sud du Sahara. Read more about Enquête sur l'utilisation du téléphone mobile pour le développement des petites et microentreprises au Ghana. Language French. Read more about Survey on the Use of Mobile Telephone for Micro and Small Business Development in Ghana. Language English.

  1. South of Sahara | Page 107 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Adapting Fishing Policy to Climate Change with the Aid of Scientific and Endogenous Knowledge (West Africa). Language English. Read more about Adaptation des politiques de pêche aux changements climatiques à l'aide des savoirs scientifiques et de connaissances ...

  2. South of Sahara | Page 64 | IDRC - International Development ...

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    South of Sahara. Sud du Sahara. Read more about La protection des renseignements personnels dans l'hémisphère sud (Protecting Privacy in the Global South) - Phase 2. Language French. Read more about Doctoral Awards to Strengthen Sub-Saharan Africa Leadership in HIV Prevention Research. Language English.

  3. South of Sahara | Page 15 | IDRC - International Development ...

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    South of Sahara. Sud du Sahara. Read more about Intensifier l'inclusion financière des femmes et des jeunes en Afrique subsaharienne. Language French. Read more about Programme de leadership sur le climat : Renforcer la résilience de l'Afrique au moyen de la recherche, des politiques et de la pratique. Language ...

  4. South of Sahara | Page 136 | IDRC - International Development ...

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    South of Sahara. Sud du Sahara. Read more about Nouveau télécentre de Manhiça (Mozambique). Language French. Read more about New Premises Assistance : Manhica Telecentre Association (Mozambique). Language English. Read more about Health Risk Analysis of Cryptosporidiosis and other Hazards in Urban ...

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    South of Sahara. Sud du Sahara. Read more about Community Exemption from Payment for Health Services (Burkina Faso). Language English. Read more about Exemption communautaire du paiement des services de santé au Burkina Faso. Language French. Read more about Études par pays dans le cadre du ...

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    South of Sahara. Sud du Sahara. Read more about Acacia Gender Learning and Capacity Strengthening. Language English. Read more about Approfondissement des connaissances et renforcement des capacités en matière de sexospécificités au sein du programme ACACIA. Language French. Read more about Soutien ...

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    South of Sahara. Sud du Sahara. Read more about Soutien institutionnel au Centre for Population and Environmental Development (CPED). Language French. Read more about Institutional Support : Centre for Population and Environmental Development (CPED). Language English. Read more about Institutional Support ...

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    South of Sahara. Sud du Sahara. Read more about Institutional Support : Centre for Research and Technology Development (RESTECH). Language English. Read more about Soutien institutionnel au Centre for Research and Technology Development (RESTECH Centre). Language French. Read more about Economic ...

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    South of Sahara. Sud du Sahara. Read more about The Economics of Adaptation and Climate-Resilient Development. Language English. Read more about Solutions d'adaptation liées aux changements climatiques et à l'eau. Language French. Read more about Examining the Economic Complexity of the Arab World to ...

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    South of Sahara. Sud du Sahara. Read more about Task Shifting for Expanding Access to Quality Eye Care Services in Ethiopia. Language English. Read more about Genre, entrepreneuriat et croissance partagée : les institutions et la promotion des petites et moyennes entreprises à Maurice et au Botswana. Language ...

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    South of Sahara. Sud du Sahara. Read more about Strengthening the Health System through a Maternal Death Review (Kenya and Zimbabwe). Language English. Read more about Taxes sur les cigarettes en Tanzanie. Language French. Read more about Cigarette Taxation in Tanzania. Language English. Read more ...

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    South of Sahara. Sud du Sahara. Read more about National Innovation Systems in Brazil, Russia, India, China and South Africa (BRICS). Language English. Read more about Strengthening the Capacity to Adapt to Climate Change in Rural Bénin. Language English. Read more about Renforcement des capacités ...

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    South of Sahara. Sud du Sahara. Read more about Civil Society and Islamism in Iraq. Language English. Read more about Société civile et islamisme en Iraq et au Maroc. Language French. Read more about Microfinance and Information and Communication Technologies : HIVOS STAR Program (Eastern and Southern ...

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    South of Sahara. Sud du Sahara. Read more about HarassMap: Using Crowdsourced Data in the Social Sciences. Language English. Read more about Mesures en matière de taxation des produits du tabac en Afrique de l'Ouest. Language French. Read more about Gemini News Service Re-launch. Language English.

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    South of Sahara. Sud du Sahara. Read more about Promoting Good Governance of Natural Resources in Post Conflict Societies. Language English. Read more about Management of Collective Rangelands in Rhamna (Morocco). Language English. Read more about Gestion des parcours dans la province de Rhamna ...

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    South of Sahara. Sud du Sahara. Read more about Innovation pharmaceutique, délivrance de brevets sur des variantes mineures et licences obligatoires. Language French. Read more about Pharmaceutical Innovation, Incremental Patenting and Compulsory Licensing. Language English. Read more about Vers une ...

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    South of Sahara. Sud du Sahara. Read more about Open Architecture, Standards and Information Systems (OASIS) for Healthcare in Africa. Language English. Read more about Gestion intégrée de l'eau, de l'assainissement et des déchets solides dans de petits centres urbains autour du lac Victoria (Kenya). Language ...

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    South of Sahara. Sud du Sahara. Read more about Open Architecture, Standards and Information Systems (OASIS) for Healthcare in Africa. Language English. Read more about Communication dans le but d'influer sur les politiques : établissement de réseaux de TIC-D en Afrique centrale, de l'Est et de l'Ouest. Language ...

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    South of Sahara. Sud du Sahara. Read more about Renforcement des stratégies locales de gestion des zones sylvo-pastorales inter villageoises dans le basin arachidier du Sénégal. Language French. Read more about Strengthening Local Strategies for Managing Inter Village Agro-pastoral Resources in the Groundnut ...

  20. No Otters in the Tassili Mountains (Sahara)

    OpenAIRE

    Smet K. de

    1987-01-01

    The Tassill Mountains are situated in the centre of the Sahara Desert and as they are rather high (summits over 2,000 m), they have a rainfall of more than 50 mm/year. There are many rivers in these mountains and although they only flow after the occasional rains, a great number of small lakes (locally called Guelta) remain in the deep canyons. Some river systems always have running water (Oued Imirhou, Oued Iherir) and most of them contain large quantities of fish (Barbus sp., Tilapia sp.) ...

  1. Presencia de perfiles lateríticos con intercalaciones atípicas y bauxitas en el sector septentrional del río Yagrumaje, Moa

    Directory of Open Access Journals (Sweden)

    Pedro S. Bergues-Garrido

    2006-03-01

    Full Text Available En el sector más septentrional del río Yagrumaje se detectaron cambios en la coloración de del  suelo, tanto a nivel de superficie como en profundidad, con presencia de flora atípica en suelos resultantes del intemperismo de las rocas ultramáficas. Los análisis corroboraron la presencia de tipos rocosos de mayor acidez a partir de los cuales se desarrollaron intercalaciones y potentes perfiles estériles para el proceso tecnológico de níquel,  manifestándose además la presencia de bauxitas de media y baja ley en la orilla oriental del río.

  2. Ethnomycological survey of traditional usage and indigenous knowledge on desert truffles among the native Sahara Desert people of Algeria.

    Science.gov (United States)

    Bradai, Lyès; Neffar, Souad; Amrani, Khaled; Bissati, Samia; Chenchouni, Haroun

    2015-03-13

    Desert truffles are edible hypogeous fungi, highly appreciated by the inhabitants of hot-desert settlements. Native Saharan people use truffles for food, promoting tourism, increasing fertility, and treatment of eye diseases and fatigue. This study consists of a cross-sectional survey focusing on the knowledge, use and ethnomycological practices of desert truffles among the native people of the Algerian Northern Sahara. The study was conducted through direct interviews with 60 truffle-hunters in the regions of Ouargla and Ghardaia. Three species were harvested and consumed by the surveyed subjects: Terfezia claveryi was the most appreciated and most expensive species, followed by Terfezia areanaria moderately preferred, then Tirmania nivea the least appreciated and least expensive. Among the 60 interviewees, 90% rely on the abundance of symbiotic plants (Helianthemum lippii) to harvest truffles, 65% begin harvesting from mid-February to March, after rains of the autumn (38%) and winter (36%), particularly in the Wadi beds (37%) and Daya landscapes (32%). Interviewees harvested truffles mainly for home consumption; however 26.7% sell any harvest surplus, and of those only 15% generate significant revenue from this source, and 73% considered the sale of desert truffles to have low financial value. Desert truffles are used in traditional medicine, especially against eye infections (22%), weakness (19%) and to promote male fertility (19%). In the case of desert truffles for consumption, the surveyed population preferred to prepare the truffles with couscous and meat, or in porridge. Respondents used price as the main criterion for deciding whether to purchase desert truffles. The surveyed trufflers use the knowledge passed from one generation to the next to help ensure a good harvest of truffles during each foray into the desert. Our findings highlight the various uses of truffles in the Sahara Desert, and how these relate to the lifestyle of local people. Copyright

  3. Explaining the Violence Pattern of the Algerian Civil War

    OpenAIRE

    Roman Hagelstein

    2008-01-01

    I draw a geographically and temporally disaggregated model of the location and course of the Algerian civil war, using new battle event and location data from press reports. I show that the war was located in areas and at moments in time in which both the rebels and the government were about equally strong, according to my novel relative strength index. Additional factors that can robustly predict high location-specific war intensity are the severity of violence at a location in the past peri...

  4. Isolation and characterization of a novel tyrosinase produced by Sahara soil actinobacteria and immobilization on nylon nanofiber membranes.

    Science.gov (United States)

    Harir, Mohammed; Bellahcene, Miloud; Baratto, Maria Camilla; Pollini, Simona; Rossolini, Gian Maria; Trabalzini, Lorenza; Fatarella, Enrico; Pogni, Rebecca

    2018-01-10

    In the present study different actinomycete strains were collected and isolated from Algerian Sahara soil with the aim to select novel enzymes with promising features for biotechnological applications. The Ms1 strain was selected, amongst the others, for its capability to produce melanin in different solid media. Ms1 chromosomal DNA was sequenced and the strain assigned to Streptomyces cyaneofuscatus sp. A tyrosinase (MW∼30kD) encoding sequence was identified and the corresponding enzyme was isolated and biochemically characterized. The tyrosinase showed the highest activity and stability at neutral and alkaline pH and it was able to oxidize l-DOPA at T=55°C and pH 7. The enzyme showed variable stability in presence of various water-miscible organic solvents, while it was inactivated by reducing agents. The tyrosinase activity was unaffected by NaCl and enhanced by different cations. Furthermore, the enzyme showed a higher specificity for diphenols than monophenols showing a higher diphenolase than monophenolase activity. Finally, tyrosinase was stabilized by immobilization on nylon nanofiber membranes with a payload of 82% when 1% glutaraldeyde was used. Taken all together, these results show that the enzyme displays interesting properties for biotechnological purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Fressignes (Indre, France, campement de chasseurs solutréens aux limites de l’extrême septentrional

    Directory of Open Access Journals (Sweden)

    Denis Vialou

    2013-11-01

    Full Text Available Hace 20000-18000 años, pobladores solutrenses se establecieron en los afloramientos de caliza de la cuenca del río Creuse, en la periferia del noroeste del Macizo Central. La excavación del yacimiento de Fressignes (Indre, Francia ha revelado una secuencia continua de ocupación en una cornisa con vistas al valle de la Creuse, cerca de veinte kilómetros al interior del macizo montañoso. Este es un campamento estacional en el que los Solutrenses llevaron consigo su sílex para debitar y tallar. Una docena de tipos petrográficos de sílex presentes en el campamento fueron definidos y sus depósitos geológicos de origen localizados hasta 100 km. Las puntas de muesca, las hojas de sauce y las piezas con retoques solutrenses han permitido caracterizar el Solutrense superior. En esta zona de contacto entre el Macizo Central y la cuenca de París, el Solutrense encuentra-se al límite extremo de su extensión hacia el norte. Esta ubicación marginal en el aspecto cultural (en el sentido clásico del término plantea preguntas acerca de una posible originalidad de Solutrense superior contra la identidad que le fue conferido en las partes más centrales y meridionales de su expansión territorial. Las excavaciones conducidas en Fressignes lograran descubrir sociedades de cazadores muy bien organizadas para explotar de la mejor forma los recursos de sus paisajes. Fressignes se convirtió en un lugar importante para el conocimiento de los últimos Solutrenses, en el extremo más septentrional de su territorio.Voici 20000-18000 ans, des Solutréens s’installèrent dans les affleurements calcaires du bassin de la Creuse, en périphérie nord ouest du Massif Central. La fouille de Fressignes (Indre, France a mis au jour une séquence continue d’occupations sur un replat dominant la vallée encaissée de la Creuse, une vingtaine de km à l’intérieur du massif montagneux. Il s’agit d’un campement saisonnier dans lequel les Solutr

  6. ETHNOBOTANICAL SURVEY OF PHOENIX DACTYLIFERA L. POLLEN USED FOR THE TREATMENT OF INFERTILITY PROBLEMS IN ALGERIAN OASES

    Science.gov (United States)

    Selmani, Cherifa; Chabane, Djamila; Bouguedoura, Nadia

    2017-01-01

    Background: The Phoenix dactylifera L. (date palm) is known for its traditional medicinal properties across the history of native population in Algerian Sahara. There is a large trend of consumption of date palm pollen preparations in many human infertility cases in our country. However, the validity has not been scientifically tested. There has been no direct scientific research on this application. This study was undertaken to identify cultivars with greater potential in the traditional medicine uses. To evaluate the effects of date palm pollen on some sexual behavioural parameters of male adult rats, we tested the role of pollen powder from Deglet Nour cultivar on some male reproductive parameters. Materials and Methods: An Ethnobotanical survey was conducted in 17 oases in southern Algeria to identify all cultivars with medicinal interest. Local people were interviewed with open questions. A questionnaire and personal interviews for data collection were designed to record important cultivars, parts used and preparations. To determine the active constituents of date palm pollen used in traditional medicine, a phytochemical screening was performed. The effects of oral administration of date palm pollen suspension on male adult rats were investigated on body and testicle weights, serum testosterone level. Results: 131 prominent cultivars were found within 12 cultivars containing various parts with medicinal effects. Some primary and secondary metabolites were detected by phytochemical screening. The pollen increased the weight of the body, testicles and enhanced the serum testosterone level of male rats treated. Conclusion: The present survey has provided the identification and recognition of date palm cultivars used in traditional Saharan medicine. Date palm pollen could improve sexual activities in male infertility cases and may be attempted to derive drugs. PMID:28480429

  7. South of Sahara | Page 160 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2015-03-31

    flexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. The Kenya National Commission for Science, Technology and Innovation (NACOSTI), in collaboration with IDRC, launched Kenya's first Research Chair on March 31, 2015 in Nairobi. Professor ...

  8. Book Review: The writings of Mauritania and the western Sahara ...

    African Journals Online (AJOL)

    Abstract. Book Title: The writings of Mauritania and the western Sahara: Arabic Literature of Africa vol. 5. Book Authors: compiled by Charles C. Stewart with Sidi Ahmed Wuld Ahmed Salim. (Leiden & Boston: Brill, 2016), 2 vols ...

  9. Literary Aftershocks of the Revolution: Recent Developments in Algerian Literature

    Directory of Open Access Journals (Sweden)

    Eric Sellin

    1980-01-01

    Full Text Available Most Algerian Francophone literature has been written since 1950, and thus the development of that literature has been intimately linked to the political events which forged the Algerian nation. Especially influential was the 1954-62 war of independence which for many years was a major contextual element in the literature. With the passage of time, the Revolution has begun to be less and less cognitive in the lives and works of the young writers. For some, Revolution lives on in the oneiric evocations of horrors glimpsed, for others it is something relegated to history, whereas for yet others it has become a political and social device. The role the Revolution plays in a writer's creativity has tended to dichotomize the literature into a conservative branch of inward- and backward-looking patriotism and a radical branch of outward- and forward-looking experimentation. Both branches present equally fervent defenses of their loyalty to their country based on a variety of arguments, but the radical branch, regardless of its relative worth in terms of internal affairs, certainly is the branch which tends to transcend national idiom and to express itself in terms of wide-spread and universal literary values.

  10. TOWARD A MINOR THEATRE: MYRIAM BEN’S ALGERIAN ANTIGONE

    Directory of Open Access Journals (Sweden)

    Kelley, Caroline

    2011-07-01

    Full Text Available In this paper, I read Myriam Ben’s Leïla, poème scénique en deux actes et un prologueas a reinterpretation of Sophocles’ Antigone. I contend that this blend of Algerian theatre, history and Greek tragedy yields a variety of ‘minor theatre’ that sets out to undermine established dramaturgical structures and prevailing historical narratives about the Algerian Revolution (1954-1962. Working in the outline of a canonical work, the playwright decentres the classic tragedyby way of a thought-provoking technical adaptation while, at the same time, refuting the fictions shrouding the events of the liberation struggle, the Front de Libération Nationale (FLN and, especially, the military overthrow of President Ahmed Ben Bella by his Defence Minister Houari Boumediene in 1965. Despite the specificity of its context, however, the allegorical nature of the play allows for a sense of universality. While its milieu is undoubtedly post-revolution Algeria, the story it communicates might take place in any country past or present –dictatorships not being limited to North Africa.

  11. Chemical composition and antioxidant activity of Algerian propolis.

    Science.gov (United States)

    Piccinelli, Anna Lisa; Mencherini, Teresa; Celano, Rita; Mouhoubi, Zina; Tamendjari, Azeddine; Aquino, Rita Patrizia; Rastrelli, Luca

    2013-05-29

    Chemical composition of propolis samples from north Algeria was characterized by chromatographic and spectroscopic analyses. High-performance liquid chromatorgaphy with diode-array detection (HPLC-DAD) fingerprint of the methanol extracts allowed the definition of two main types of Algerian propolis (AP) directly related to their secondary metabolite composition. Investigation of two representative types of AP by preparative chromatographic procedure and mass spectrometric (MS) and NMR techniques led to the identification of their main constituents: caffeate esters and flavonoids from an AP type rich in phenolic compounds (PAP) and labdane and clerodane diterpenes, together with a polymethoxyflavonol, from an AP type containing mainly diterpenes (DAP). Subsequently, two specific HPLC-MS/MS methods for detection of PAP and DAP markers were developed to study the chemical composition of propolis samples of different north Algerian regions. Antioxidant activity of AP samples was evaluated by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) assay, and a significant free-radical scavenging effect was observed for propolis of the PAP series rich in polyphenols.

  12. Accumulated Testimony: Layering French Girls’ Diaries on the Algerian Exodus

    Directory of Open Access Journals (Sweden)

    Amy L Hubbell

    2014-01-01

    Full Text Available In 1997, French-Algerian author Leïla Sebbar published an illustrated children’s book, J’étais enfant en Algérie, juin 1962 (‘I was a child in Algeria, June 1962’ in which she creates the fictional account of a young girl from the interior of Algeria leaving her home during the great exodus of the French just prior to Algerian independence. Using the genre of diary writing, Sebbar’s text reads as testimonial of fleeing their country for a homeland they do not know. Although this text is intimate, Sebbar relies on accumulated scraps of collective experience that, when joined to her own, fill in the absence of her homeland. In 2013, French artist Nicole Guiraud published her personal diaries kept before and during her exodus from Algeria from April to July 1962. Her raw representation of traumatic upheaval is couched in a rich paratext including artwork, photographs, and German translations, that simultaneously intensifies her account and distracts the reader from the extreme pain behind her words. In this article I demonstrate how fictional and real accounts published in very different historical contexts convey the exodus experienced by almost one million individuals and how each author deploys a layering technique to simultaneously draw in and distance the reader from extraordinarily painful personal experience.

  13. South of Sahara | Page 47 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Outils cliniques simplifiés et stratégie de formation à l'intention des travailleurs de la santé. Language French. Read more about Renforcement du rôle de la société civile dans la gouvernance de l'eau dans trois villes africaines, Durban, Maputo et Nairobi. Language ...

  14. South of Sahara | Page 74 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Renforcement de la recherche en santé en Afrique de l'Ouest. Language French. Read more about Production durable de légumes sous-utilisés en vue d'améliorer la sécurité alimentaire en milieu rural (FCRSAI). Language French. Read more about Participation des ...

  15. South of Sahara | Page 6 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Subventions et bourses en faveur de l'égalité des sexes et du développement des innovations numériques. Language French. Read more about Réseaux d'accès communautaire : faire accéder à Internet un milliard de personnes de plus. Language French. Read more ...

  16. South of Sahara | Page 67 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Les dimensions économiques de l'adaptation et du développement résilient aux aléas du climat. Language French. Read more about Renforcement des capacités de réaliser des examens systématiques. Language French. Read more about Lutte intégrée contre les ...

  17. South of Sahara | Page 81 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    South of Sahara. Sud du Sahara. Read more about Synthèse des enseignements en matière d'adaptation aux changements climatiques. Language French. Read more about de liens entre systèmes d'information sur la santé pour assurer l'efficacité du processus décisionnel (Afrique de l'Est). Language French. Read more ...

  18. BRCA1 and BRCA2 Germline Mutations Screening in Algerian Breast/Ovarian Cancer Families

    Directory of Open Access Journals (Sweden)

    Farid Cherbal

    2010-01-01

    Full Text Available Background: Breast cancer is the leading cause of cancer death in women in Algeria. The contribution of BRCA1 and BRCA2 mutations to hereditary breast/ovarian cancer in Algerian population is largely unknown. Here, we describe analysis of BRCA1 and BRCA2 genes in 86 individuals from 70 families from an Algerian cohort with a personal and family history suggestive of genetic predisposition to breast cancer.

  19. Paleohydrology and paleoenvironments at Bir Sahara: Pleistocene lithostratigraphy and sedimentology in the southern Egyptian Sahara

    Science.gov (United States)

    Hill, Christopher L.; Schild, Romuald

    2017-12-01

    The Bir Sahara area contains a remarkable record of Middle and Late Pleistocene hydrologic and environmental conditions for Saharan North Africa, based on lithostratigraphic and sedimentologic evidence from basin-fill deposits. Some of the deposits contain Lower Paleolithic (Acheulean) or Middle Paleolithic artifacts that help to constrain their age, since Acheulian artifacts are assigned to the Middle Pleistocene, while Middle Paleolithic artifacts are limited to either the Middle or Late Pleistocene. Locality BS-14 is in the southern part of Bir Sahara, while localities E-88-15, E-88-2, BS-13, and BS-16 are situated in the south-central part of the deflational basin, closer to the present-day water-hole. Lowered groundwater conditions during arid intervals resulted in erosional topographic basins. These deflational basins were later filled with sediments associated with wetter hydrologic conditions. The oldest studied sedimentary sequence in the Bir Sahara depression (BS-14) contains in situ Acheulian artifacts. Acheulian handaxes are found in sands underlying carbonates that are interpreted as evidence of spring-fed pond and marsh environments during a Middle Pleistocene wet interval. At the E-88-15 locality, the stratigraphic sequence documents deposition in a possible perennial pond or small lake that varied in extent and depth and is associated with Middle Paleolithic artifacts. At E-88-12 and BS-13, lateral and vertical variations in the lithofacies of the basin-fill sediments provide additional records of changing hydrologic conditions during the Late Pleistocene. These hydrologic conditions appear to reflect variations in water-table levels related to groundwater recharge and, at times, local rains.

  20. PREFACE: 1st Franco-Algerian Workshop on Neutrino Physics

    Science.gov (United States)

    Mebarki, N.; Mimouni, J.; Vanucci, F.; Aissaoui, H.

    2015-04-01

    The first Franco-Algerian workshop on neutrino physics was held on 22-23 October 2013 at the University of Mentouri, Constantine, Algeria. It was jointly organized by the Laboratory of Mathematical and Subatomic Physics (LPMS) and the Direction of Scientific Research (DGRSTD) for the Algerian side, and for the French part by the IN2P3, CNRS and CEA IRFU. It is one of a series of international scientific meetings organized every two years by the LPMS at Constantine on high energy physics (theoretical, nuclear physics, classical and quantum cosmology, astrophysics, mathematical physics and quantum computing etc...) to maintain a high quality in scientific research and education at Algerian universities. This specific meeting brought together experts in particle physics, astrophysics and cosmology from France and Algeria. It touched upon several theoretical, phenomenological as well as experimental aspects of the neutrinos. The workshop participants were mostly young researchers from many universities and research institutes in Algeria. The physics of neutrinos is a very active field in particle physics, hence the importance for the High Energy community in Algeria to gain expertise in this ''strategic'' area at the intersection of various topics in theoretical physics and high energy astrophysics (SM physics, CP violation, in general, SNe explosions, baryogenesis...). The neutrino proposed by Pauli back in 1930 as a ''desperate remedy'' to save the law of energy conservation in beta decay had a bright early history. Discovered in 1956 in the Cowan-Reines experiment despite all odds, this elusive particle which enabled us to understand the chiral nature of the weak interactions which later lead to the electro-weak unification finally appears to hold a key role in understanding subatomic physics as well as the structure and structuration of the Universe. It is also, after the discovery of the Higgs particle at the LHC in 2012, the only grey area left today in the

  1. THE IMPACT OF THE GLOBAL FINANCIAL CRISIS ON ALGERIAN ECONOMY

    Directory of Open Access Journals (Sweden)

    Zeyneb GUELLIL

    2015-04-01

    Full Text Available The Global Economic Crisis and 2008 financial crisis, is considered by many economists the worst financial crisis since the Great Depression of the 1930s , The financial crisis, brewing for a while, really started to show its effects in the middle of 2007 and into 2008. It is a situation where macro indicator like economic growth rate fall in most countries across the world. “Although economists largely failed to predict this global economic seismic shock, they have since made up for their oversight by generating a large and growing literature explaining the crisis.” In this discussion paper explores what happened and what issues arise from the Global Financial Crisis on the global economy and the Algerian economic in particular.

  2. Modeling the synergistic antibacterial effects of honey characteristics of different botanical origins from the Sahara Desert of Algeria

    Directory of Open Access Journals (Sweden)

    Hadda eLAALLAM

    2015-11-01

    Full Text Available Background: Honey has multiple therapeutic properties due to its composition with diverse components.Objectives: This study aims to investigate the antimicrobial efficacy of Saharan honeys against bacterial pathogens, the variation of honey floral origins and its physicochemical characteristics.Materials and Methods: The antimicrobial activity of 32 samples of honey collected from the Algerian Sahara Desert was tested on four pathogenic bacteria; Bacillus subtilis, Clostridium perfringens, Escherichia coli and Staphylococcus aureus. The botanical origin of honeys and their physicochemical properties were determined and their combined antibacterial effects were modeled using a generalized linear mixed model (GLMM.Results: Out of the 32 study samples, 14 were monofloral and 18 were multifloral. The pollen density was on average 7.86 × 106 grains/10 g of honey, water content was 14.6%, electrical conductivity was 0.5 μS/cm, pH was 4.38±0 50, hydroxymethylfurfural content was 82 mg/kg of honey, total sugars = 83%, reducing sugars = 71%, and the concentration of proline = 525.5±550.2 mg/kg of honey. GLMM revealed that the antibacterial effect of honey varied significantly between bacteria and floral origins. This effect increased with increasing of water content and reducing sugars in honey, but it significantly decreased with increase of honey electrical conductivity. E. coli was the most sensitive species with an inhibition zone of 10.1±4.7 mm, while C. perfringens was the less sensitive with 3.9±5.4 mm. Honeys dominated by pollen of Fabaceae sp. were most effective with an overall antimicrobial activity equals to 13.5±4.7 mm.Conclusion: Saharan honeys, of certain botanical origins, have physicochemical and pollinic characteristics with relevant potential for antibacterial purposes. This encourages a more comprehensive characterization of honeys with in vivo and in vitro investigations.Keywords: Honey characterization; antibacterial effects

  3. Helga-Jane Scarwell et Isabelle Roussel (dir., 2010, Le changement climatique : Quand le climat nous pousse à changer d’ère, Presses Universitaire du Septentrion, Lille, 358 pages

    Directory of Open Access Journals (Sweden)

    Laurence Rocher

    2010-12-01

    Full Text Available L’ouvrage « Le changement climatique. Quand le climat nous pousse à changer d’ère », édité par les Presses Universitaire du Septentrion dans la collection Environnement et société, coordonné par Helga-Jane Scarwell et Isabelle Roussel, rassemble autour de la question du changement climatique plusieurs contributions de chercheurs en géographie, pour la plupart membres du laboratoire TVES de Lille. Ce livre apporte un éclairage original et intéressant, alliant des études de cas comportant un fo...

  4. Cita más septentrional del cangrejo portúnido pantropical Cronius ruber en el Atlántico oriental (Islas Canarias): ¿expansión natural o por causas antropogénicas?

    OpenAIRE

    González, José A.; Triay-Portella, Raül; Escribano, Aitor; Cuesta, José A.

    2017-01-01

    El cangrejo pantropical Cronius ruber (Lamarck, 1818) (Brachyura: Portunidae) es citado por primera vez en las Islas Canarias. Previamente conocido de las Islas Cabo Verde y Senegal, el presente constituye el registro más septentrional de esta especie en el Atlántico oriental. Los cangrejos fueron recolectados mediante un arte de trampa (pequeña nasa usada para muestreo en aguas someras) y posteriormente identificados a partir de sus caracteres morfológicos y mediante código de barras genétic...

  5. Alternative energies. Sahara Power needs pan-European grid operator

    Energy Technology Data Exchange (ETDEWEB)

    Van Wijland, G.

    2009-09-15

    A consortium of leading European - mostly German - companies plans to invest 400 billion euros in a megaproject to generate solar power in the Sahara desert. Desertec, as the project is called, could cover 15 percent of European electricity demand. The problem is, how do you transport this power to Paris and Berlin? It can only work with a pan-European grid operator.

  6. Solar power at the edge of the Sahara desert

    Energy Technology Data Exchange (ETDEWEB)

    Bresler, Ines

    2012-07-01

    In Morocco, the turn in the energy sector is overseen by His Majesty the King himself: in 2009, the King introduced the Moroccan Solar Plan and created the Moroccan Agency for Solar Energy (MASEN) for its implementation. This year, the construction work for the first project complex will commence at the edge of the Sahara desert. (orig.)

  7. South of Sahara | Page 9 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    flexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. Pages. « first · ‹ previous … 2 · 3 · 4 · 5 · 6 · 7 · 8; 9; 10 · next › · last » · What we do · Funding · Resources · About IDRC. Knowledge. Innovation. Solutions.

  8. Obituary: Dr Dimitri Tassiopoulos | Phaswana-Mafuya | SAHARA-J ...

    African Journals Online (AJOL)

    SAHARA-J: Journal of Social Aspects of HIV/AIDS. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 14, No 1 (2017) >. Log in or Register to get access to full text downloads.

  9. South of Sahara | Page 5 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Tiyatien Health frontline health workers conducting baseline community health survey. Photo: Direct Relief. Health systems in developing countries face huge challenges in providing high-quality, affordable services. Among them are geographic barriers, a shortage of skilled personnel, and poor data.

  10. The Sources Of Protracted Conflict In The Western Sahara

    Science.gov (United States)

    2016-03-01

    1. History Leading up to the Occupation .......................................16 2. Spanish Decolonization (1956–1976...has weathered major geopolitical storms that have changed the political landscape of the world; it has outlasted the Cold War and survived the...across from Spanish shores, allowing the passage of one the most important gas and oil pipelines feeding Europe.33 The waters of the Western Sahara

  11. Africa, Sub-Sahara: A Selected Functional and Country Bibliography.

    Science.gov (United States)

    Foreign Service (Dept. of State), Washington, DC. Foreign Service Inst.

    Sub-Sahara Africa is covered in this bibliography prepared for use in training programs. Consisting of nearly 500 citations which date from 1940 to the present, topics covered include: POPULATION, Traditional Cultures, Religion, Art, Literature, History, Colonialism, Economic Development, Agricultural Modernization, Education and Manpower,…

  12. Managing AIDS stigma | Holzemer | SAHARA-J: Journal of Social ...

    African Journals Online (AJOL)

    SAHARA-J: Journal of Social Aspects of HIV/AIDS. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 1, No 3 (2004) >. Log in or Register to get access to full text downloads.

  13. Modeling the synergistic antibacterial effects of honey characteristics of different botanical origins from the Sahara Desert of Algeria.

    Science.gov (United States)

    Laallam, Hadda; Boughediri, Larbi; Bissati, Samia; Menasria, Taha; Mouzaoui, Mohamed S; Hadjadj, Soumia; Hammoudi, Rokia; Chenchouni, Haroun

    2015-01-01

    Honey has multiple therapeutic properties due to its composition with diverse components. This study aims to investigate the antimicrobial efficacy of Saharan honeys against bacterial pathogens, the variation of honey floral origins, and its physicochemical characteristics. The antimicrobial activity of 32 samples of honey collected from the Algerian Sahara Desert was tested on four bacteria; Bacillus subtilis, Clostridium perfringens, Escherichia coli, and Staphylococcus aureus. The botanical origin of honeys and their physicochemical properties were determined and their combined antibacterial effects were modeled using a generalized linear mixed model (GLMM). Out of the 32 study samples, 14 were monofloral and 18 were multifloral. The pollen density was on average 7.86 × 10(6) grains/10 g of honey, water content was 14.6%, electrical conductivity (EC) was 0.5 μS/cm, pH was 4.38 ± 0 50, hydroxymethylfurfural (HMF) content was 82 mg/kg of honey, total sugars = 83%, reducing sugars = 71%, and the concentration of proline = 525.5 ± 550.2 mg/kg of honey. GLMM revealed that the antibacterial effect of honey varied significantly between bacteria and floral origins. This effect increased with increasing of water content and reducing sugars in honey, but it significantly decreased with increase of honey EC. E. coli was the most sensitive species with an inhibition zone of 10.1 ± 4.7 mm, while C. perfringens was the less sensitive. Honeys dominated by pollen of Fabaceae sp. were most effective with an overall antimicrobial activity equals to 13.5 ± 4.7 mm. Saharan honeys, of certain botanical origins, have physicochemical and pollinic characteristics with relevant potential for antibacterial purposes. This encourages a more comprehensive characterization of honeys with in vivo and in vitro investigations.

  14. Modeling the synergistic antibacterial effects of honey characteristics of different botanical origins from the Sahara Desert of Algeria

    Science.gov (United States)

    Laallam, Hadda; Boughediri, Larbi; Bissati, Samia; Menasria, Taha; Mouzaoui, Mohamed S.; Hadjadj, Soumia; Hammoudi, Rokia; Chenchouni, Haroun

    2015-01-01

    Background: Honey has multiple therapeutic properties due to its composition with diverse components. Objectives: This study aims to investigate the antimicrobial efficacy of Saharan honeys against bacterial pathogens, the variation of honey floral origins, and its physicochemical characteristics. Materials and Methods: The antimicrobial activity of 32 samples of honey collected from the Algerian Sahara Desert was tested on four bacteria; Bacillus subtilis, Clostridium perfringens, Escherichia coli, and Staphylococcus aureus. The botanical origin of honeys and their physicochemical properties were determined and their combined antibacterial effects were modeled using a generalized linear mixed model (GLMM). Results: Out of the 32 study samples, 14 were monofloral and 18 were multifloral. The pollen density was on average 7.86 × 106 grains/10 g of honey, water content was 14.6%, electrical conductivity (EC) was 0.5 μS/cm, pH was 4.38 ± 0 50, hydroxymethylfurfural (HMF) content was 82 mg/kg of honey, total sugars = 83%, reducing sugars = 71%, and the concentration of proline = 525.5 ± 550.2 mg/kg of honey. GLMM revealed that the antibacterial effect of honey varied significantly between bacteria and floral origins. This effect increased with increasing of water content and reducing sugars in honey, but it significantly decreased with increase of honey EC. E. coli was the most sensitive species with an inhibition zone of 10.1 ± 4.7 mm, while C. perfringens was the less sensitive. Honeys dominated by pollen of Fabaceae sp. were most effective with an overall antimicrobial activity equals to 13.5 ± 4.7 mm. Conclusion: Saharan honeys, of certain botanical origins, have physicochemical and pollinic characteristics with relevant potential for antibacterial purposes. This encourages a more comprehensive characterization of honeys with in vivo and in vitro investigations. PMID:26594206

  15. Essential oils from Algerian species of Mentha as new bio-control agents against phytopathogen strains.

    Science.gov (United States)

    Benomari, Fatima Zahra; Andreu, Vanessa; Kotarba, Jules; Dib, Mohammed El Amine; Bertrand, Cédric; Muselli, Alain; Costa, Jean; Djabou, Nassim

    2017-09-02

    Chemical composition and antifungal activity of essential oils of Algerian Mentha species were studied. Chemical compositions of different Mentha species oils (Mentha rotundifolia, M. spicata, M. pulegium, and M. piperita) were investigated by capillary GC and GC/MS, and their antifungal activities were evaluated by means of paper disc diffusion method and minimum inhibitory concentration (MIC) assays. In total, 98 components from all Mentha species were identified. All oils were rich in monoterpene-oxygenated components. In addition, we reported fumigant antifungal activity of Algerian Mentha essential oils against four fungi: Botrytis cinerea, Penicillium expansum, Monilinia laxa, and M. fructigena. All oils demonstrated very good inhibition especially against B. cinerea, M. laxa, and M. fructigena. Both Monilinia fungi were extremely sensitive to all Algerian Mentha oils, which suggests that Mentha essential oils have the potential to be used as bio-pesticides to protect fruit trees, such as apple and pear trees, and provides an alternative to chemical pesticides.

  16. Rentierism in the Algerian economy based on oil and natural gas

    International Nuclear Information System (INIS)

    Machin Alvarez, Alejandra

    2010-01-01

    This essay analyzes Algeria's degree of adaptation toward possessing the constituent features of an oil and gas rentier economy, and whether its current status could be threatened by changes to its energy policy. With this aim, the article first uses empirical evidence to analyze different rentier features of the Algerian economy (the importance of the hydrocarbon sector, Algerian NOC Sonatrach's role in energy policy and revenue distribution). Second, the circuit that perpetuates rentier logic is described, the main conclusion being that the Algerian economy does indeed offer the very conditions that guarantee the self-perpetuation of rentierism. However, this conclusion is jeopardized by uncertainties stemming from two potential changes in the national status of the hydrocarbons sector: a greater presence of foreign hydrocarbon companies in Algeria, and growing internationalization by Sonatrach.

  17. Rentierism in the Algerian economy based on oil and natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Machin Alvarez, Alejandra [Grupo de Investigacion sobre Economia Politica de la Mundializacion, Departamento de Economia Aplicada I, Facultad de Ciencias Economicas y Empresariales, Universidad Complutense de Madrid, Campus de Somosaguas, 28223 Madrid (Spain)

    2010-10-15

    This essay analyzes Algeria's degree of adaptation toward possessing the constituent features of an oil and gas rentier economy, and whether its current status could be threatened by changes to its energy policy. With this aim, the article first uses empirical evidence to analyze different rentier features of the Algerian economy (the importance of the hydrocarbon sector, Algerian NOC Sonatrach's role in energy policy and revenue distribution). Second, the circuit that perpetuates rentier logic is described, the main conclusion being that the Algerian economy does indeed offer the very conditions that guarantee the self-perpetuation of rentierism. However, this conclusion is jeopardized by uncertainties stemming from two potential changes in the national status of the hydrocarbons sector: a greater presence of foreign hydrocarbon companies in Algeria, and growing internationalization by Sonatrach. (author)

  18. The production of diaspora: Algerian emigration from colonialism to neo-colonialism (1840-1970).

    Science.gov (United States)

    Samers, M

    1997-01-01

    "This paper is part of a larger project investigating the production and regulation of North African immigrants in the greater Paris automobile industry. Its aims are twofold. First, to reverse the emphasis placed on immigrants in the receiving countries and to (re-)explore the historical production of Algerian emigration into metropolitan industry, more specifically within the automobile industry....Second, in adopting an ¿articulation of modes of production' (AMOP) narrative as an alternative to other Eurocentric approaches, the first part of this paper emphasizes the contradictory layering of various modes which have produced an Algerian colonial diaspora. The latter half of the paper argues that the history of post-independence Algeria confirms that emigration was reinforced through a complex neocolonial relationship during a period of rapid acceleration of Algerian migration to France." excerpt

  19. Essential oil of Algerian Eucalyptus citriodora: Chemical composition, antifungal activity.

    Science.gov (United States)

    Tolba, H; Moghrani, H; Benelmouffok, A; Kellou, D; Maachi, R

    2015-12-01

    Essential oil of Eucalyptus citriodora is a natural product which has been attributed for various medicinal uses. In the present investigation, E. citriodora essential oil was used to evaluate its antifungal effect against medically important dermatophytes. Essential oil from the Algerian E. citriodora leaves was analyzed by GC and GC/MS. The antifungal effect of E. citriodora essential oil was evaluated against four dermatophytes: Microsporum canis, Microsporum gypseum, Trichophyton mentagrophytes, Trichophyton rubrum using disc diffusion method, disc volatilization method, and agar dilution method. The chemical composition of the oil revealed the presence of 22 compounds accounting for 95.27% of the oil. The dominant compounds were citronellal (69.77%), citronellol (10.63%) and isopulegol (4.66%). The disc diffusion method, MIC and MFC determination, indicated that E. citriodora essential oil had a higher antifungal potential against the tested strains with inhibition zone diameter which varied from (12 to 90mm) and MIC and MFC values ranged from (0.6 to 5μL/mL and 1.25 to 5μL/mL) respectively. The M. gypseum was the most resistant to the oil. The results of the present study indicated that E. citriodora essential oil may be used as a new antifungal agent recommended by the pharmaceutical industries. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  20. Reproductive performance of male rabbits of algerian local population

    Directory of Open Access Journals (Sweden)

    Cherfaoui DJ

    2013-06-01

    Full Text Available A total of 267 rabbit does and 46 bucks from a local Algerian population were controlled during 6 generations (from G0 to G5 at the experimental farm of the University of Tizi-Ouzou. Natural mating was used and 1412 presentations were analysed. Reproductive and growing performance were analysedtaking into account the effect of the buck, its age, the generation, the season of mating (or kindling and the physiological status of does at the moment of the mating. The buck influenced the acceptance rate(P<0.001, kindling rate (P=0.032, litter size at birth and at weaning (P<0.001, litter weight at birth (P<0.001and at weaning (P=0.034, the mean weaning weight (P=0.018 and consequently the ponderal productivity at weaning (weight of rabbits produced at weaning/mating, P<0.001. Nevertheless, the ponderal productivity was also influenced by the age of bucks, the generation, the season and the physiological status of does at the moment of mating. The highest acceptation rate was recorded in autumn in non lactating does (primiparous and multiparous. Productivity was higher for bucks 5-10 mo old but decreased thereafter.Productivity was higher in spring, particularly for multiparous and lactating does and highly varied with the generation, evidencing the importance of environmental conditions.

  1. The study of the cumulative effects of the application of urban sewage sludge on an eroded soil cultivated in the Algerian steppe

    Science.gov (United States)

    Boutmedjet, Ahmed; Boukkaya, Nassira; Houyou, zohra; Ouakid, Mohamed; Bielders, Charles

    2014-05-01

    Since the seventies, desertification is one of the major problems faced by the Mediterranean climate regions. These problems are inherent in the soil and climate characteristics of these regions, but their magnitude and acuity depend mainly on human activities. The process of desertification that affects more and more land is more pronounced as soil degradation, which accelerates constantly reduced resources farmland and pasture. Especially in areas bordering the Sahara, as the Algerian steppe, a real belt between the Sahara and the Algerian tell As part of the study of the cumulative effect of the application of urban sewage sludge on sandy soil and culture that is a cereal (barley), we had results that enabled us to identify some precepts,. The short-term effects studied in this experiment indicate that the amendment of the sewage sludge had a beneficial effect on the fertilizing qualities of the soil and therefore the performance of barley. To observations of Culture (barley), indicate that the best grain yield was obtained with D3 (28.76 quintals / ha) and D2 (33.91 quintals / ha). This is due to the effect of the sludge by the addition of required nutrients crop production. The lowest yield (24.11 quintals / ha) being obtained for the control (D0). It is the same for straw yield, with 47.5 quintals / ha in D2. The D3 treatment (30 t / ha) has previously presented the best results, but after 3 years we noticed that the best yields are obtained with D2 (10 t / ha). Except the pH and the rate of limestone that are related to changes in the characteristics of the site, there was an improvement in some physical and chemical properties of the soil. The contributions of sewage sludge amended greater quality soil biology D2 (number and effective species collected). Increasing the organic matter content (1.45%) and electrical conductivity (0.18 microseconds / cm) in the soil is only significant for the highest dose (30t/ha), although a tendency to enrichment in

  2. The Algerian Seismic Network: Performance from data quality analysis

    Science.gov (United States)

    Yelles, Abdelkarim; Allili, Toufik; Alili, Azouaou

    2013-04-01

    densify the network and to enhance performance of the Algerian Digital Seismic Network.

  3. Safety Culture Assessment in Petrochemical Industry: A Comparative Study of Two Algerian Plants

    Directory of Open Access Journals (Sweden)

    Assia Boughaba

    2014-06-01

    Conclusion: The comparison between the two petrochemical plants of the group Sonatrach confirms these results in which Company A, the managers of which are English and Norwegian, distinguishes itself by the maturity of their safety culture has significantly higher evaluations than the company B, who is constituted of Algerian staff, in terms of safety management practices and safety performance.

  4. Effect of a Long Term Treatment by Algerian Propolis Flavonoids on ...

    African Journals Online (AJOL)

    Our study carried out in vivo, using liver mitochondria isolated from albinos rats, treats the effect of a long term treatment by Algerian propolis ethanolic extract and their flavonic aglycones and glycosides to the amount of 100 mg/kg on mitochondrial antioxidant-prooxidant balance. Our results showed that all extracts ...

  5. Why Algerian Students Struggle to Achieve in English Literature: An Appraisal of Possible Root Causes

    Science.gov (United States)

    Bouazid, Tayeb; Le Roux, Cheryl S.

    2014-01-01

    This article examines the challenges experienced by Arabic-speaking students and lecturers at meeting the proposed learning outcomes in English Literature (EL) at a residential university in Algeria. An overview of the history of foreign languages (French and English) in the curricula in Algerian schools and tertiary education institutions has…

  6. Losing the Moral Compass: Torture and ’Guerre Revolutionnaire’ in the Algerian War

    Science.gov (United States)

    2006-01-01

    the unusual French interest in Algeria was its large European population. These inhabitants, know as the pied noirs or co- lons, were European...increasingly smaller groups to avoid detection and retain mobility. Every time the Algerians attempted to move to phase-three operations—conventional operations

  7. Anticyclonic eddy energy and pathways in the Algerian basin (1993-2007)

    Science.gov (United States)

    Pessini, Federica; Perilli, Angelo; Olita, Antonio

    2016-04-01

    The Algero-Provençal basin plays a key role in the circulation of the entire Mediterranean Sea. Consequently, in the past its hydrodynamics has been intensively studied with infrared and colour satellite imagery, moorings, surface drifters and altimetry observations. The basin is divided into two sub-basins by the North Balearic front, a thermal front characterized by a high seasonal variability: the Provençal sub-basin in the north and the Algerian sub-basin in the south. The Algerian basin is dominated by mesoscale phenomena, especially anti-cyclonic eddies. The Algerian current becomes unstable and meanders; often giving rise to mesoscale eddies of both signs. The anti-cyclonic eddies (hereafter Algerian Eddies or AEs) can grow rapidly in horizontal and vertical extension. They can also detach from the Algerian slope and circulate for several months within the sub-basin, while the cyclonic ones quickly disappear. In spite of its limited dimensions, the Algerian sub-basin can contain as many as three long-life AEs, which can interact with each other and with sub-basin dynamics. In spite of the current body of research, a study on the tracking, energy and interaction of these long-life eddies in time and space is still lacking. In order to fill this gap, we applied the automated eddy detection and tracking method created by Penven (2005), which reveals the complex movements and dynamics of eddies in the Algerian sub-basin. The Penven algorithm combines the detection of the largest closed contours in SSH (Sea Surface Height) with a positive value of the relevant Okubo-Weiss parameter. The latter has already been successfully used in the Algerian Basin by Isern-Fontanet et al. (2003). The eddy-tracking algorithm is based on the minimization of a general distance that takes into account the difference in coordinates, radius, vorticity, mean height and amplitude between eddies of consecutive temporal steps. The code was modified and adapted in order to optimize its

  8. Shock veins in the Sahara 02500 ordinary chondrite

    OpenAIRE

    Owocki, Krzysztof; Muszyński, Andrzej

    2012-01-01

    A specimen of the Sahara 02500 ordinary chondrite contains shock-produced veins consisting of recrystallised fine- grained pyroxenes that include small droplets of Ni-rich metal. Non-melted olivines and pyroxenes show planar deformations filled by shock-melted and -polluted metal and troilite. Shock-melted feldspathic glass is present close to the shock veins. Geothermometric estimations indicate that the meteorite locally experienced moderate shock metamorphism with a minimum loc...

  9. Sahara Coal: the fine art of collecting fines for profit

    Energy Technology Data Exchange (ETDEWEB)

    Schreckengost, D.; Arnold, D.

    1984-09-01

    A considerable increase in the volume of fines in rom coal caused Sahara Coal in Illinois to redesign the fine coal system in their Harrisburg preparation plant. Details of the new design, and particularly the fine refuse system which dewaters and dries 28 mesh x O clean coal, are given. Results have exceeded expectations in reducing product losses, operating costs and slurry pond cleaning costs.

  10. South of Sahara | Page 82 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    flexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. La persistance de la pauvreté en Afrique subsaharienne, dans le contexte de progression rapide de la mondialisation et de la libéralisation des échanges commerciaux des deux dernières décennies, a suscité énormément de débats en ...

  11. Fennec dust forecast intercomparison over the Sahara in June 2011

    Directory of Open Access Journals (Sweden)

    J.-P. Chaboureau

    2016-06-01

    Full Text Available In the framework of the Fennec international programme, a field campaign was conducted in June 2011 over the western Sahara. It led to the first observational data set ever obtained that documents the dynamics, thermodynamics and composition of the Saharan atmospheric boundary layer (SABL under the influence of the heat low. In support to the aircraft operation, four dust forecasts were run daily at low and high resolutions with convection-parameterizing and convection-permitting models, respectively. The unique airborne and ground-based data sets allowed the first ever intercomparison of dust forecasts over the western Sahara. At monthly scale, large aerosol optical depths (AODs were forecast over the Sahara, a feature observed by satellite retrievals but with different magnitudes. The AOD intensity was correctly predicted by the high-resolution models, while it was underestimated by the low-resolution models. This was partly because of the generation of strong near-surface wind associated with thunderstorm-related density currents that could only be reproduced by models representing convection explicitly. Such models yield emissions mainly in the afternoon that dominate the total emission over the western fringes of the Adrar des Iforas and the Aïr Mountains in the high-resolution forecasts. Over the western Sahara, where the harmattan contributes up to 80 % of dust emission, all the models were successful in forecasting the deep well-mixed SABL. Some of them, however, missed the large near-surface dust concentration generated by density currents and low-level winds. This feature, observed repeatedly by the airborne lidar, was partly forecast by one high-resolution model only.

  12. The Green Sahara: Climate Change, Hydrologic History and Human Occupation

    Science.gov (United States)

    Blom, Ronald G.; Farr, Tom G.; Feynmann, Joan; Ruzmaikin, Alexander; Paillou, Philippe

    2009-01-01

    Archaeology can provide insight into interactions of climate change and human activities in sensitive areas such as the Sahara, to the benefit of both disciplines. Such analyses can help set bounds on climate change projections, perhaps identify elements of tipping points, and provide constraints on models. The opportunity exists to more precisely constrain the relationship of natural solar and climate interactions, improving understanding of present and future anthropogenic forcing. We are beginning to explore the relationship of human occupation of the Sahara and long-term solar irradiance variations synergetic with changes in atmospheric-ocean circulation patterns. Archaeological and climate records for the last 12 K years are gaining adequate precision to make such comparisons possible. We employ a range of climate records taken over the globe (e.g. Antarctica, Greenland, Cariaco Basin, West African Ocean cores, records from caves) to identify the timing and spatial patterns affecting Saharan climate to compare with archaeological records. We see correlation in changing ocean temperature patterns approx. contemporaneous with drying of the Sahara approx. 6K years BP. The role of radar images and other remote sensing in this work includes providing a geographically comprehensive geomorphic overview of this key area. Such coverage is becoming available from the Japanese PALSAR radar system, which can guide field work to collect archaeological and climatic data to further constrain the climate change chronology and link to models. Our initial remote sensing efforts concentrate on the Gilf Kebir area of Egypt.

  13. Sahara Coal: the fine art of collecting fines for profit

    Energy Technology Data Exchange (ETDEWEB)

    Schreckengost, D.; Arnold, D.

    1984-09-01

    Because of a change in underground mining methods that caused a considerable increase in the amount of fine sizes in the raw coal, Sahara Coal Co. designed and constructed a unique and simple fine coal system at their Harrisburg, IL prep plant. Before the new system was built, the overload of the fine coal circuit created a cost crunch due to loss of salable coal to slurry ponds, slurry pond cleaning costs, and operating and maintenance costs--each and every one excessive. Motivated by these problems, Sahara designed a prototype system to dewater the minus 28 mesh refuse. The success of the idea permitted fine refuse to be loaded onto the coarse refuse belt. Sahara also realized a large reduction in pond cleaning costs. After a period of testing, an expanded version of the refuse system was installed to dewater and dry the 28 mesh X 0 clean coal. Clean coal output increased about 30 tph. Cost savings justified the expenditures for the refuse and clean coal systems. These benefits, combined with increased coal sales revenue, paid back the project costs in less than a year.

  14. SILURIAN – DEVONIAN OF THE ORIENTAL ALGERIAN SAHARA: implication of new field data from Tassili n'Ajjer outcrops and Berkine Basin (SE, Algeria) for shale gas exploration.

    OpenAIRE

    Djouder, Hocine; Boulvain, Frédéric; Da Silva, Anne-Christine; Musial, Geoffray; Murat, Bruno; Lüning, Sebastian

    2015-01-01

    The Silurian – Devonian succession have been deposited in wide sags and sub-basins in a cratonic setting, along the northwestern passive margin of the Gondwana during the opening of the proto-Tethyan ocean. During this Siluro-Devonian Period, a high subsidence occurs stacked sediment bodies and organic-rich shales were deposited in many places that respectively form important hydrocarbon reservoirs and source rocks throughout North Africa basins and Arabia (Boot et al., 1998 ; Lüning et al...

  15. Geological lineament mapping in arid area by semi-automatic extraction from satellite images: example at the El Kseïbat region (Algerian Sahara)

    Energy Technology Data Exchange (ETDEWEB)

    Hammad, N.; Djidel, M.; Maabedi, N.

    2016-07-01

    Geologists in charge of a detailed lineament mapping in arid and desert area, face the extent of the land and the abundance of eolian deposits. This study presents a semi-automatic approach of extraction of lineament, different from other methods, such as the automatic extraction and manual extraction, by being both fast and objective. It consists of a series of digital processing (textural and spatial filtering, binarization by thresholding and mathematic morphology ... etc.) applied to a Landsat 7 ETM+scene. This semi-automatic approach has produced a detailed map of lineaments, while taking account of tectonic directions recognized in the region. It helps mitigate the effect of dune deposits meet the specifications of arid environment. The visual validation of these linear structures, by geoscientists and field data, allowed the identification of the majority of structural lineaments or at least those tried geological. (Author)

  16. A volcanic district between the Hoggar uplift and the Tenere Rifts: Volcanology, geochemistry and age of the In-Ezzane lavas (Algerian Sahara)

    Science.gov (United States)

    Yahiaoui, Rachid; Dautria, Jean-Marie; Alard, Olivier; Bosch, Delphine; Azzouni-Sekkal, Abla; Bodinier, Jean-Louis

    2014-04-01

    The In-Ezzane volcanic district (EZD), located at the triple junction of Algeria, Niger and Libya belongs to the Eastern Hoggar, covers 350 km2 and includes 9 volcanic edifices that are probably aligned along NW-SE faults, parallel to the Tafassasset valley. The low volume (0.7 and 1 km3) of emitted lavas, the similar morphology of the monogenic cones and the lack of differentiated rocks indicate that the volcanic activity of the EZD was restricted in time and volume. The new K-Ar age (i.e. 2.86 ± 0.07 Ma) indicates that the EZD is contemporaneous with the last alkali volcanism paroxysm in Hoggar and with the nearby Libyan volcanics. The EZD alkali basalts (mainly basanite) show a remarkable homogeneous compositions both in major elements (44.8 ⩽ SiO2 ⩽ 45.8 wt.%; 5.2 ⩽ (Na2O + K2O) ⩽ 6.2 wt.%), trace elements (4.3 ⩽ Th ⩽ 5.5 ppm; 34.7 ⩽ La ⩽ 44.7 ppm; 16.1 < La/Yb(N) < 21.6) and radiogenic isotopes (0.70285 < 87Sr/86Sr < 0.70303; 0.51298 < 143Nd/144Nd < 0.51301; (19.212 < 206Pb/204Pb < 19.340, 15.589 < 207Pb/204Pb < 15.602 and 38.834 < 208Pb/204Pb < 38.903). Relative to the Hoggar alkaly basalts the EZD basalts appear systematically impoverished in incompatible elements and show a depleted signature both in Sr and Nd isotopes (almost MORB-like). The Pb isotopes are relatively enriched and intermediate between tholeiites and alkali basalts of the Hoggar. This unusual geochemical signature, is uneasy to reconcile with the known characteristics of the Hoggar swell, and would rather fingerprint a circum cratonic mantle lying beneath the west border of the Murzuq craton (Libya).

  17. Quantifying the role of sandy-silty sediments in generating slope failures during earthquakes: example from the Algerian margin

    OpenAIRE

    Dan, Gabriela; Sultan, Nabil; Savoye, Bruno; Deverchere, Jacques; Yelles, Karim

    2009-01-01

    International audience; The Algerian margin is a seismically active region, where during the last century, several large magnitude earthquakes took place. This study combines geotechnical and sedimentological data with numerical modelling to quantitatively assess the present-day slope stability of the Algerian margin. Geotechnical laboratory tests, such as cyclic triaxial tests, oedometric tests and vane shear tests were carried out on sediment cores collected on the study area. The liquefact...

  18. Sud du Sahara | Page 59 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Health Financing and Benefit Incidence Analysis in Uganda and Zambia. Langue English. Read more about Le Centre d'innovation pour la résilience de l'Afrique de l'Est. Langue French. Read more about Climate Change and Water Adaptation Options. Langue English.

  19. Child Survival in sub Sahara Africa: the role of CAPGAN and ...

    African Journals Online (AJOL)

    Child Survival in sub Sahara Africa: the role of. CAPGAN and regional child health practitioners & scientists ... liberate the world from poverty. Child Survival is the direct goal of MDG 4, and strongly and ... fate of the children in sub Sahara Africa (sSA) is worse and the MDG 4 and 5 are regressing . Superimposed on this.

  20. Sud du Sahara | Page 200 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about TTI Phase 2 Institutional Support: Economic Policy Research Centre. Langue English. Read more about TTI Phase 2 Institutional Support: Science, Technology and Innovation Policy Research Organization. Langue English. Read more about Relations entre les think tanks ...

  1. Sud du Sahara | Page 211 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Travaux de l'Health Enterprise Architecture Laboratory (HEAL). Langue French. Read more about Health Enterprise Architecture Laboratory (HEAL). Langue English. Read more about African Climate Change Fellowship Program - Phase II. Langue English. Read more ...

  2. Sud du Sahara | Page 111 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Equity Gauge Zambia : Enhancing Governance, Equity and Health. Langue English. Read more about Human Resources for Health Research in Africa. Langue English. Read more about Ressources humaines pour la recherche en santé en Afrique. Langue French.

  3. Regime shifts in the Sahara and Sahel: interactions between ecological and climatic systems in northern Africa

    NARCIS (Netherlands)

    Foley, J.A.; Coe, M.T.; Scheffer, M.; Wang, G.L.

    2003-01-01

    The Sahara and Sahel regions of northern Africa have complex environmental histories punctuated by sudden and dramatic "regime shifts" in climate and ecological conditions. Here we review the current understanding of the causes and consequences of two environmental regime shifts in the Sahara and

  4. Sud du Sahara | Page 219 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Recours à la délégation des tâches pour accroître la prestation de services essentiels en chirurgie en Ouganda. Langue French. Read more about Expanding Provision of Essential Surgical Services through Task Shifting (Uganda). Langue English. Read more about ...

  5. Sud du Sahara | Page 228 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Equinet : réappropriation des ressources aux fins de la santé - phase V. Langue French. Read more about EQUINET : Reclaiming the Resources for Health - Phase V. Langue English. Read more about Remittances to Conflict Zones : the Sudanese Diaspora in Cairo ...

  6. Sud du Sahara | Page 55 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Strengthening the Health System through a Maternal Death Review (Kenya and Zimbabwe). Langue English. Read more about Taxes sur les cigarettes en Tanzanie. Langue French. Read more about Cigarette Taxation in Tanzania. Langue English. Read more about AIDS ...

  7. Sud du Sahara | Page 268 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Taxes sur les cigarettes en Tanzanie. Langue French. Read more about Cigarette Taxation in Tanzania. Langue English. Read more about Vers une structure de sécurité régionale dans la Corne de l'Afrique - phase II. Langue French. Read more about Toward a Regional ...

  8. Sud du Sahara | Page 232 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Démarches novatrices en ce qui a trait à la délégation des tâches en santé mentale. Langue French. Read more about Institutional Support: Centre for Economic and Social Research, Education and Documentation (Burkina Faso). Langue English. Read more about ...

  9. Sud du Sahara | Page 247 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Publishing and Alternative Licensing Model of Africa (PALM Africa). Langue English. Read more about Strategic Action Plan for ERNWACA - 2007-2011. Langue English. Read more about Plan d'action stratégique du ROCARE - 2007-2011. Langue French. Read more ...

  10. Sud du Sahara | Page 191 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Ethical Medical and Biomedical Practice in Health Research in Africa. Langue English. Read more about Canada-Africa Research Exchange Grants (CAREG) : Pilot Phase. Langue English. Read more about Subventions pour la coopération en recherche entre le Canada ...

  11. Optimal investment and indifference pricing when risk aversion is not monotone: SAHARA utility functions

    NARCIS (Netherlands)

    Chen, A.; Pelsser, A.; Vellekoop, M.

    2008-01-01

    Abstract. We develop a new class of utility functions, SAHARA utility, with the dis- tinguishing feature that they implement the assumption that agents may become less risk-averse for very low values of wealth. This means that SAHARA utility can be used to characterize risk gambling behavior of an

  12. Sud du Sahara | Page 199 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Improving Internet Governance: Support to the Global Commission on Internet Governance. Langue English. Read more about The State of Young Scholars and Scientists in Africa. Langue English. Read more about Doctoral Awards to Strengthen Sub-Saharan Africa ...

  13. Conflict resolution in Western Sahara | Solà-Martín | African Journal ...

    African Journals Online (AJOL)

    This paper examines the democratisation agenda laid out by Western governments for the North African region vis-à-vis their Realpolitik conflict containment approach towards the Western Sahara conflict. Western policymakers conceive the United Nations Mission for the Referendum in Western Sahara as a safety net that ...

  14. Seismic vulnerability: theory and application to Algerian buildings

    Science.gov (United States)

    Mebarki, Ahmed; Boukri, Mehdi; Laribi, Abderrahmane; Farsi, Mohammed; Belazougui, Mohamed; Kharchi, Fattoum

    2014-04-01

    results to the observed damages. For pre-earthquake analysis, the methodology widely used around the world relies on the prior calibration of the seismic response of the structures under given expected scenarios. As the structural response is governed by the constitutive materials and structural typology as well as the seismic input and soil conditions, the damage prediction depends intimately on the accuracy of the so-called fragility curve and response spectrum established for each type of structure (RC framed structures, confined or unconfined masonry, etc.) and soil (hard rock, soft soil, etc.). In the present study, the adaptation to Algerian buildings concerns the specific soil conditions as well as the structural dynamic response. The theoretical prediction of the expected damages is helpful for the calibration of the methodology. Thousands (˜3,700) of real structures and the damages caused by the earthquake (Algeria, Boumerdes: Mw = 6.8, May 21, 2003) are considered for the a posteriori calibration and validation process. The theoretical predictions show the importance of the elastic response spectrum, the local soil conditions, and the structural typology. Although the observed and predicted categories of damage are close, it appears that the existing form used for the visual damage inspection would still require further improvements, in order to allow easy evaluation and identification of the damage level. These methods coupled to databases, and GIS tools could be helpful for the local and technical authorities during the post-earthquake evaluation process: real time information on the damage extent at urban or regional scales as well as the extent of losses and the required resources for reconstruction, evacuation, strengthening, etc.

  15. Wars and conflicts in the Sahara-Sahel

    DEFF Research Database (Denmark)

    Walther, Olivier

    the traditional lines between what is local and global, military and civilian, domestic and international, politics and identity. The purpose of this paper is to analyse these patterns of violence. The first section presents the geographic distribution and development over time of the main sources of violence...... in North and West Africa before examining the events behind the increase in political violence in the Sahel and the Sahara. The second section analyses the patterns of violence, and focuses on the geographic scales thereof and the strategies of the warring parties. In its conclusion, the paper highlights...

  16. The new Algerian law project about hydrocarbons: Sonatrach reinforced in a competitive environment

    International Nuclear Information System (INIS)

    Mebtoul, A.

    2002-01-01

    At the time of the transposition of the first gas directive in French law and of the start up of a new phase of the liberalization of the natural gas market in the European Union, it is useful to have an idea of the opinion of the supplying countries in this domain. In the coming years, the gas dependence of the European Union with respect to the producing countries will increase. Thus, the relations with these countries will change progressively with the new context defined by the second directive. Among the gas producing countries, Algeria is a close and faithful partner of France and Europe. The expected evolutions of its hydrocarbons sector show its adaptation will to the competitive context and its wish of partnership reinforcement with European gas companies. This article presents an analysis of the Algerian project of hydrocarbons law made by an Algerian expert of this sector. (J.S.)

  17. Hierarchical Classification for Spoken Arabic Dialect Identification using Prosody: Case of Algerian Dialects

    OpenAIRE

    Bougrine, Soumia; Cherroun, Hadda; Ziadi, Djelloul

    2017-01-01

    In daily communications, Arabs use local dialects which are hard to identify automatically using conventional classification methods. The dialect identification challenging task becomes more complicated when dealing with an under-resourced dialects belonging to a same county/region. In this paper, we start by analyzing statistically Algerian dialects in order to capture their specificities related to prosody information which are extracted at utterance level after a coarse-grained consonant/v...

  18. Effect of Algerian Varieties Dates on Glycemic, Arterial Blood Pressure and Satiety Responses

    OpenAIRE

    Gourchala Freha, Mihoub Fatma, Derradj Meriem, Henchiri Cherifa

    2016-01-01

    The purpose of our study is to determine the Glycemic Indexes (GIs)of three Algerians varieties of dates in healthy subjects, evaluate the satiety and effect on arterial pressure after their consumption. We have first documented the chemical composition of the dates. 10 healthy subjects consumed the dates (carbohydrates content of 50 g) in order to determine the GIs. The responses of glycaemia were monitored during two hours after the dates taking and compared to the reference glucose. In a r...

  19. Antimicrobial activity of Algerian propolis in foodborne pathogens and its quantitative chemical composition

    Directory of Open Access Journals (Sweden)

    Neila Nedji

    2014-12-01

    Full Text Available Objective: To evaluate the antimicrobial activity of propolis samples collected from different regions of Algeria and their chemical composition. Methods: The antibacterial activity of ethanolic extract of Algerian propolis against Bacillus cereus (IPA, Staphylococcus aureus (ATCC25923R, Escherichia coli (ATCC25922 and Pseudomonas aeruginosa (ATCC27893R was evaluated by the disc diffusion method and determined as an equivalent of the inhibition zones diameters after incubation of the cultures at 37 °C for 24 h. The investigation of the polyphenol and flavonoid contents was done spectrophotometrically. Results: The ethanolic extract of Algerian propolis samples inhibited the growth of all examined microorganisms with the highest antimicrobial activity against the Gram-positive bacteria. Polyphenol and flavonoids contents were variable, depending on the propolis samples and a positive correlation between antimicrobial activity and chemical composition was observed. Conclusions: Antimicrobial activity, polyphenol and flavonoid contents were variable, depending on the propolis sample. The strong antimicrobial activity of Algerian propolis may be due to high total phenolic and flavonoid contents and this study suggests potential use of propolis in foods.

  20. Physicochemical and microbiological study of “shmen”, a traditional butter made from camel milk in the Sahara (Algeria: isolation and identification of lactic acid bacteria and yeasts

    Directory of Open Access Journals (Sweden)

    Mourad, Kacem

    2006-06-01

    Full Text Available Microorganisms (aerobic bacteria, coliforms, lactic acid bacteria, psychrotrophs, lipolytic bacteria and yeasts were isolated from 20 samples of shmen, a traditional clarified butter made from sour camel milk in the Algerian Sahara. The values of pH, titratable acidity, NaCl, total solid, moisture, and fat content ranged from : 3.11-4.97, 0.19-0.36%, 1.04-2.15%, 64.03-65.11%, 34.40-34.99%, and 49.90-56% respectively. A total of 181 isolates of lactic acid bacteria were identified as Lactobacillus plantarum (40 strains, Lactobacillus delbrueckii ssp. bulgaricus (35 strains, Lactococcus lactis ssp. lactis biovar diacetylacti (22 strains, Lactococcus lactis ssp. cremoris (18 strains, Lactobacillus paracasei ssp. paracasei (10 strains, Leuconostoc pseudomesenteroides (9 strains and Leuconostoc gelidum (12 strains Enterococcus faecium (35 strains. Yeasts were isolated from all samples (55 isolates. Of these, 40 were identified as Saccharomyces cerevisiae and 15 isolates were identified as Saccharomyces sp.Se aislaron los microorganismos (bacterias aeróbicas, coliformes, bacterias acido lácticas, bacterias lipolíticas y levaduras de 20 muestras de “shmen”, una matequilla tradicional del Sahara argelino hecha a partir de leche de camella. Los valores de pH, acidez, libre, Nacl, solidos totales, humedad y grasa oscilaron entre 3,11-4,97, 0,19-0,36%, 1.04-2,15%, 64,03-65,11%, 34,40-34,99% y 49,90-56,00%, respectivamente. Entre los 181 cultivos puros de bacterias lácticas se identificaron Lactobacillus plantarum (40 cepas, Lactobacillus delbrueckii ssp. bulgaricus (35 cepas, Lactococcus lactis ssp. lactis biovar diacetylacti (22 cepas, Lactococcus lactis ssp. cremoris (18 cepas, Lactobacillus paracasei ssp. paracasei (10 cepas, Leuconostoc pseudomesenteroides (9 cepas and Leuconostoc gelidum (12cepas Enterococcus faecium (35 cepas. Asimismo, se detectaron levaduras en todas las muestras (55 cultivos puros. De estos, 40 se identificaron como

  1. Dry Deposition from Sahara Sources Regions of Western Africa

    Directory of Open Access Journals (Sweden)

    B. Douaiba

    2014-01-01

    Full Text Available Sahara dust storms during March 2004 have attracted much attention from the dust-research community due to their intensity, wide coverage, and endurance. In the present work, the dry deposition mechanisms of mineral dust are analysed during an event on the 3 March 2004 over the Northwest African coast. This particular case was chosen based on the strong dry removal that occurred, rendering it ideal for examining the deposition processes. The simulation of synoptic conditions and dry deposition of four dust particles including clay, small silt, large silt, and sand was performed with Eta model, coupled with a desert dust cycle module. The results have been compared with surface data from weather stations in North Africa, data of dry metals from stations located in Gran Canaria, and various satellite images such as European Organization for the Exploitation of Meteorological Satellites and Moderate Resolution Imaging Spectroradiometer for the period in question.

  2. Eastern Sahara Geology from Orbital Radar: Potential Analog to Mars

    Science.gov (United States)

    Farr, T. G.; Paillou, P.; Heggy, E.

    2004-01-01

    Much of the surface of Mars has been intensely reworked by aeolian processes and key evidence about the history of the Martian environment seems to be hidden beneath a widespread layer of debris (paleo lakes and rivers, faults, impact craters). In the same way, the recent geological and hydrological history of the eastern Sahara is still mainly hidden under large regions of wind-blown sand which represent a possible terrestrial analog to Mars. The subsurface geology there is generally invisible to optical remote sensing techniques, but radar images obtained from the Shuttle Imaging Radar (SIR) missions were able to penetrate the superficial sand layer to reveal parts of paleohydrological networks in southern Egypt.

  3. The copper-silver occurrences of Rahmani, Western Sahara, Algeria

    Science.gov (United States)

    Fuchs, Y.; Arbey, F.; Bouima, T.

    1996-05-01

    The copper-silver occurrences of Rahmani (Western Sahara, Algeria) are located in paleochannel facies of Cambrian sandstones deposited on Pan-African volcanics and intrusives. Sulfur isotope analyses were performed on pyrite and copper sulfides in order to trace the origin of the copper-silver mineralization. S isotopic data preclude that bacterial reduction of Cambrian sulfate could have induced the formation of the sulfides. Non-bacterial reduction of sulfate during burial diagenesis is the most valuable explanation for disseminated pyrite. Isotopic ratios on copper sulfides indicate that they result from the reaction of actual or subactual sulfate-bearing surface water with the disseminated pyrite. The origin of copper and silver remains unclear. They are thought to be brought by the downward migrating surface water but their origin could be either the leaching of the Cambrian sandstones or of the weathered volcanics.

  4. Shock veins in the Sahara 02500 ordinary chondrite

    Science.gov (United States)

    Owocki, Krzysztof; Muszyński, Andrzej

    2012-08-01

    A specimen of the Sahara 02500 ordinary chondrite contains shock-produced veins consisting of recrystallised fine-grained pyroxenes that include small droplets of Ni-rich metal. Non-melted olivines and pyroxenes show planar deformations filled by shock-melted and -polluted metal and troilite. Shock-melted feldspathic glass is present close to the shock veins. Geothermometric estimations indicate that the meteorite locally experienced moderate shock metamorphism with a minimum local peak temperature above 1400°C, resulting in partial melting of Ca-poor pyroxene and full melting of feldspars, metal and sulphides. The mineral assemblage in the shock veins suggests a pressure during melt recrystallisation below 10 GPa.

  5. SAHARA-J: Journal of Social Aspects of HIV/AIDS

    African Journals Online (AJOL)

    SAHARA J Journal of Social Aspects of HIV/AIDS Research Alliance. ... counselling, impact, mitigation, stigma, discrimination, prevention, treatment, adherence, culture, faith-based approaches, evidence-based intervention, health communication, structural and environmental intervention, financing, policy, media, etc).

  6. Sud du Sahara | Page 144 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2015-03-31

    flexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. The Kenya National Commission for Science, Technology and Innovation (NACOSTI), in collaboration with IDRC, launched Kenya's first Research Chair on March 31, 2015 in Nairobi. Professor ...

  7. Sud du Sahara | Page 202 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Lutte intégrée contre les maladies humaines et animales pour les bergers contraints à la sédentarisation en Tanzanie. Langue French. Read more about Les dimensions économiques de l'adaptation et du développement résilient aux aléas du climat. Langue French.

  8. Sud du Sahara | Page 175 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Sud du Sahara. Read more about Centre of Excellence for Civil Registration and Vital Statistics (CRVS) Systems. Langue English. Read more about Accorder l'accès aux données économiques pour prévenir les maladies liées au tabac et à l'alcool en Afrique. Langue French. Read more about Améliorer le ...

  9. Algerian medical teachers' research output and its determinants during the 2000-2009 decade.

    Science.gov (United States)

    Bezzaoucha, A; Atif, M L; Bouamra, A; El Kebboub, A; Benzerga, M; Ben Abdelaziz, A; Soulimane, A; Ladner, J; Borgès Da Silva, G; Meguenni, K; Quessar, A; Heroual, N; Bouguizi, A; Boussouf, N; Makhlouf, F; Lamdjadani, N; Tibiche, A; Abbassene, S; Regagba, D; Benameur, M

    2014-02-01

    Publications are the primary output of scientific research. We conducted a national study to quantify Algerian medical teachers' research output and identify its determinants during the 2000-2009 decade. The American Medline database and the French Pascal database were used. A publication was eligible only if the lead author was an Algerian medical teacher (in medicine, pharmacy, or dentistry) working in Algeria. The same questionnaire was completed by cases (teachers who were first authors of an original article during the study period) and randomly selected controls. Logistic regression analysis was used to identify factors related to research output. A total of 79 original articles (42.2% of publications) were retrieved, a quarter of which were listed in Pascal alone. The publication rate was 2.6 original articles per 1000 teachers per year. The journals that published these original articles had a median impact factor of 0.83. The ability to publish an original article was 4.3 times higher if the teacher had undergone training in biostatistics and/or epidemiology (adjusted odds ratio [aOR]=4.31, 95% confidence interval [CI]: 1.79-10.38). A promotion evaluation grid that did not encourage writing (aOR=3.44, 95% CI: 1.42-8.33), a doctoral thesis, seniority, foreign collaboration, and English language proficiency were found to be associated with publication output. Algerian medical teachers' research output was particularly low. Replacing the current promotion grid with a grid that promotes writing, developing abilities to read and write articles and developing English language proficiency are likely to improve this situation. Copyright © 2014. Published by Elsevier Masson SAS.

  10. Algerian watermelon mosaic virus (AWMV): a new potyvirus species in the PRSV cluster.

    Science.gov (United States)

    Yakoubi, Soumaya; Lecoq, Hervé; Desbiez, Cécile

    2008-08-01

    A potyvirus was isolated from a naturally infected squash plant in Algeria in 1986. Biological and serological data have revealed that the virus, initially described as H4, is related to other cucurbit-infecting potyviruses, particularly Moroccan watermelon mosaic virus (MWMV) and Papaya ringspot virus (PRSV). To establish unequivocally the taxonomic status of H4, its full-length genome sequence was established. H4 shared identities of 70% and 65% at the amino acid level with MWMV and PRSV, respectively, indicating that H4 is a distinct species of the PRSV cluster. The name Algerian watermelon mosaic virus (AWMV) is proposed for this new potyvirus species.

  11. The Economics of Colonialism: Hunger, Expropriation and Mendicancy in Mohammed Dib's Algerian Trilogy

    Directory of Open Access Journals (Sweden)

    Benjamin J Sparks

    2016-01-01

    Full Text Available The colonial endeavor as argued by Aimé Césaire in his Discourse on Colonialism is neither an evangelization, nor a philanthropic enterprise, nor an aid system to combat systems of ignorance, sickness, and tyranny (32. It is a system of power relations based on exploitation and violence without concern for the Other. To borrow Césaire’s term, colonialism is nothing other than chosification ; it makes objects of people, tearing them from their land, home, and families, depriving them of essential, life-providing commodities. Colonization’s social and economic policies disrupted traditional society and the Algerian way of life more so than the physical military conquests had done. Albert Camus, as a Pied-Noir author, provides an outsider’s perspective on the suffering of the Algerian population, declaring, “Pour aujourd’hui, j’arrête ici cette promenade à travers la souffrance et la faim d’un peuple. On aura senti du moins que la misère ici n’est pas une formule ni un thème de méditation. Elle est. Elle crie et elle désespère. Encore une fois, qu’avons-nous fait pour elle et avons-nous le droit de nous détourner d’elle ?” (Camus 40 ‘For now, I must end this survey of the suffering and hunger of an entire population. The reader will have seen, at least, that misery here is not just a word or a theme for meditation. It exists. It cries out in desperation. What have we done about it, and do we have the right to avert our eyes.’ Mohammed Dib’s Algerian trilogy gives flesh to Camus’s statement; misery in these novels shouts and despairs, it shows itself through the characters and narration. This literature shows, as only literature can, the Algerians’ misery, and their desperation; it creates a collective trauma to be shared and understood by many through the act of storytelling. This collective trauma brings out the emotions of the characters and allows the reader to feel empathy toward the plight of the

  12. Antimicrobial activity of Algerian honey on subclinical mastitis pathogens isolated from goat's milk

    Directory of Open Access Journals (Sweden)

    A. Bourabah

    2014-04-01

    Full Text Available Aim: The aim of the present study was to determine the susceptibility of subclinical mastitis pathogens isolated from goat's milk and to evaluate the antimicrobial activity of Algerian honey on mastitis causing bacteria. Materials and Methods: The antibacterial activity against the isolated bacteria was evaluated by determining the Minimal Inhibitory Concentration (MIC, using the agar incorporation method. Results: The results showed that both Micrococcus spp. and Klebsiella spp. were susceptible to Streptomycin and tetracycline, while Pseudomonas aeruginosa, E coli, Enterobacter spp., Bacillus spp., and Coagulase Negative Staphyloccoci (CNS were preferentially susceptible to Streptomycin. However, Streptococcus D was the most resistant to the tested antibiotics whereas Staphylococcus aureus was the most susceptible to all the studied antibiotics. As regards to the antimicrobial activity of honey, the measured values were comprised between 11 and 14%. Conclusion: The results reveal that antimicrobial drugs susceptibility tests in goat subclinical mastitis might be necessary before the treatment. Algerian honey exhibited in vitro antimicrobial activity against different isolated bacteria in goat mastitis.

  13. Diet, Lifestyles, Family History, and Prostate Cancer Incidence in an East Algerian Patient Group

    Science.gov (United States)

    Lassed, Somia; Deus, Cláudia M.; Lourenço, Nuno; Dahdouh, Abderrezak

    2016-01-01

    Prostate cancer (PC) is the fourth most common cancer in men and the sixth leading cause of death in Algeria. To examine the relationship between lifestyle factors, including diet, and family history and PC risk, a case-control study was performed in an eastern Algerian population, comprising 90 patients with histologically confirmed PC and 190 controls. Data collection was carried out through a structured questionnaire and statistical analysis was performed to evaluate the different variables. The data showed that consumption of lamb and beef meat and high intake of animal fat and dairy products increased PC risk. Seven to thirteen vegetables servings per week and fourteen or more servings decreased PC risk by 62% and 96%, respectively. Seven to fourteen fruit servings per week decrease PC risk by 98%. Green tea consumption reduced the risk of PC but the results were statistically borderline. Increased risk was observed for individuals with family history of PC in first and in second degree. A positive strong association was also found for alcohol and smoking intake and a dose-response relationship existed for quantity and history of smoking. This study suggests that dietary habits, lifestyle factors, and family history have influence on the development of PC in Algerian population. PMID:27975054

  14. Hair-zinc levels determination in Algerian psoriatics using Instrumental Neutron Activation Analysis (INAA)

    International Nuclear Information System (INIS)

    Mansouri, A.; Hamidatou Alghem, L.; Beladel, B.; Mokhtari, O.E.K.; Bendaas, A.; Benamar, M.E.A.

    2013-01-01

    Psoriasis is a multifactorial skin disease with an unknown etiology. Zinc has a positive impact on psoriasis. The aim of this study is to determine hair-zinc concentration in Algerian psoriatics. 58 psoriatics and 31 normal controls of both genders were selected. Hair zinc levels were determined using Instrumental Neutron Activation Analysis technique (INAA). Student's t-test and One-Way ANOVA were applied. The average zinc concentration for controls and patients were 152±53 μg/g and 167±52 μg/g respectively. They are not significantly different (p>0.05). Zn concentration for males and females controls and patients were 171±27 μg/g, 151±37 μg/g and 145±59 μg/g, 178±58 μg/g respectively. However, for females we have observed a significant difference (p<0.05). - Highlights: ► Psoriasis is a multifactorial skin disease with an unknown etiology. ► About 2–5% of global population in the world suffers from psoriasis. ► The aim of this study is to determine hair-zinc concentration in Algerian psoriatics. ► The average zinc concentration for controls and patients were 152±53 μg/g and 167±52 μg/g respectively.

  15. [Primary evaluation of the behaviour eating disorder in obese and type 2 diabetic Algerian subjects].

    Science.gov (United States)

    Koceïr, E A; Benbaïbeche, H; Haffaf, M; Kacimi, G; Oudjit, B

    2009-01-01

    Glucose imbalance in type 2 diabetes and massive weight gain in obese subjects are disorders that are correlated with Behaviour Eating Disorder (BED), leading to a hypercaloric, sweet and fat oriented diet. This study examined how BED such as dietary restriction, disinhibition, and hunger, are assessed by Three Factor Eating Questionnaire (TFEQ) and Dutch Eating Behaviour Questionnaire (DEBQ). In the present investigation these factors were studied in a sample of Algerian population composed of 30 obese subjects, 70 type 2 diabetic patients and 30 healthy subjects. 51 questions or items were used for the TFEQ test and 33 questions for the DEBQ test. Multivariate analysis showed that restriction and disinhibition were significantly associated with obesity and diabetes pathogenesis. Compared to healthy subjects, obese patients showed a significant hyperphagic BED type (disinhibition and hunger disorders). These BED are associated with psycho-sensory disorders as characterized by externality and emotivity. Conversely, the diabetic patient showed both hypophagic and hyperphagic BED. In this study, the role of BED in obesity genesis and in glycaemia dysregulation of the diabetes pathology seems to be confirmed. An early identification of these disorders deserves further investigation in a broad Algerian population in order to treat them.

  16. NON BANKING FINANCIAL COMPANIES AND INDIA’S RURAL ECONOMY - WITH REFERENCE TO SAHARA GROUP

    Directory of Open Access Journals (Sweden)

    SUKANTA CHANDRA SWAIN

    2012-10-01

    Full Text Available Sahara India Group has diversified business in the areas like finance, real estate, media and entertainment, tourism and services. Its business in finance, as usual, comes under the purview of Reserve Bank of India (RBI jurisdiction. Its two financial institutions (FIs – Sahara India Investment Corporation Ltd (SIICL, a non-banking finance company (NBFC and Sahara India Financial Corporation Ltd (SIFCL, a residuary nonbanking finance company (RNBC have been coming under RBI scanner. While the registration of SIICL has been recently cancelled by RBI in spite of a net profit in 2006-07 against a loss in 2005-06, SIFCL has been under the threat of winding up the business owing to regulatory concerns of RBI. Thus time will come when Sahara India Group will no more be there in the financial sector. However, it will not allow the resources withdrawn from these two FIs to be idle. As it has been a prominent player in the real estate industry of India, it is clearly visible that it will reallocate the resources in favour of real estate. That way, the profitability of Sahara India Group will never be undermined. But can we say with confident that the economy will never lose anything by this ‘move by coercion’ of Sahara India Group? Certainly no, because other FIs are yet to penetrate into rural areas what SIICL and SIFCL had been doing successfully. Therefore the twin objective - Mobilization of rural savings and eradication of rural poverty will definitely be in jolt because of this. This paper tries to analyze critically this ‘move by coercion’ of Sahara India Group in the perspective of rural poverty, the ultimate problem of Indian Economy.

  17. Monitoring the Algerian Basin through glider observations, satellite altimetry and numerical simulations along a SARAL/AltiKa track

    Science.gov (United States)

    Aulicino, G.; Cotroneo, Y.; Ruiz, S.; Sánchez Román, A.; Pascual, A.; Fusco, G.; Tintoré, J.; Budillon, G.

    2018-03-01

    The Algerian Basin is a key component of the general circulation in the Western Mediterranean Sea. The presence of both fresh Atlantic water and more saline Mediterranean water gives the basin an intense inflow/outflow regime and complex circulation patterns. Energetic mesoscale structures that evolve from meanders of the Algerian Current into isolated cyclonic and anticyclonic eddies dominate the area, with marked repercussions on biological activity. Despite its remarkable importance, this region and its variability are still poorly known and basin-wide knowledge of its meso- and submesoscale features is still incomplete. Studying such complex processes requires a synergistic approach that involves integrated observing systems. In recent years, several studies have demonstrated the advantages of combined use of autonomous underwater vehicles, such as gliders, with a new generation of satellite altimetry. In this context, we present results of an observational program conducted in the Algerian Basin during fall 2014 and 2015 that aimed to advance our knowledge of its main features. The study was carried out through analysis of high resolution glider observations, collected along the Algerian BAsin Circulation Unmanned Survey (ABACUS) chokepoint, in synergy with co-located SARAL/AltiKa altimetric products and CMEMS numerical simulations. Results show that glider-derived dynamic height and SARAL/AltiKa absolute dynamic topography have similar patterns, with RMS of the differences ranging between 1.11 and 2.90 cm. Even though larger discrepancies are observed near the Balearic and Algerian coasts, correlation coefficients between glider and satellite observations seem mostly to be affected by reduced synopticity between the measurements. Glider observations acquired during the four surveys reveal the presence of several water masses of Atlantic and Mediterranean origin (i.e., AW and LIW at different modification levels) with marked seasonal variability.

  18. Environmental isotopes in the aquifers of the North Western Sahara

    International Nuclear Information System (INIS)

    Conrad, G.

    1975-09-01

    The isotopic composition of single rains at Beni-Abbes (Algeria) has been determined from 1964 to 1975. The weighed mean delta 18 O value is -3.54 %o vs. SMOW for all rains, -6.29 for rains higher than 10 mm. Only these more intense rains are believed to contribute significantly to groundwater recharge. Tritium content of precipitation varies from 900 TU in a 1964 rain, to 235 in 1967, 215 in 1968 and about 50 in 1972. The isotopic and chemical composition of water from a small salt lake nearby Beni-Abbes show variations depending on the evaporation rate and on the amount and origin of inflow. Groundwater in the Western Ground Erg contain significant amount of tritium, indicating recent recharge. The water is however submitted to evaporation as indicated by its 18 O and deuterium content. The so-called Continental Intercalaire aquifer, which extends over most of the Sahara desert, appears to be presently recharged in the outcropping areas like in Tidikelt, as shown by tritium and 14 C, and by the Western Ground Erg aquifer in the Gourara area, as shown by stable isotopes

  19. The New Oil-Related Issues in the Sahara

    International Nuclear Information System (INIS)

    Auge, Benjamin

    2011-01-01

    The Sahara is one of the last African regions to remain under-explored by oil companies. After the swift rise in crude oil prices about a decade ago, the land-locked nature of the terrain, the main hurdle standing in the way of exploration, had been overcome thanks to an exponential growth in sums set aside for exploration. The arrival on the scene of State enterprises, especially from China, also made profitability secondary to the pressing need to find new reserves. A study of the state of affairs in Mauritania, Mali, Niger, and Chad discloses how the situation differs from case to case. Some are already producing like Mauritania, albeit in small quantities, and Chad, which is the sole net exporter of the region, whereas Niger will begin producing in 2012 and Mali has not had a single well drilled for decades due to its haphazard choice of oil companies. The four States mentioned do not cooperate in any way in the oil sector even though this ought to be essential in a zone that has such special peculiarities in terms of climate, geography, and security as it is facing the threat of Al Qaeda in the Islamic Maghreb (AQMI) and the Tuareg

  20. Aplicación de análisis petrológicos para determinar la procedencia de artefactos líricos: metodología y resultados obtenidos en la Patagonia septentrional argentina

    Directory of Open Access Journals (Sweden)

    Alicia S. SANGUINETTI

    2009-12-01

    Full Text Available RESUMEN: Se seleccionaron muestras de materiales líticos superficiales y estratigráficos, procedentes de sitios arqueológicos ubicados sobre ambas márgenes del río Limay entre las localidades de Paso Flores y Piedra del Águila, en la provincia de Río Negro, Patagonia septentrional argentina.Teniendo en cuenta su abundancia y semejanza macroscópica con el material típico de la Cantera- Taller Paso Limay, destacado sitio local, se planteó determinar si se trataba de la misma materia prima y, así, evaluar la distribución regional de la misma utilizando análisis petrográficos y geoquímicos. La aplicación de estas clásicas técnicas petrológicas constituyen la metodología por la cual se logran establecer las características distintivas y detalladas para este material lírico, identificándolo así como una importante y ampliamente utilizada materia prima en la región.ABSTRACT: At Northern Patagonia, Río Negro Province, Argentina, from archeological sites over both margins of Limay River, between Paso Flores and Piedra del Águila localities, surface and stratigraphie lithic materials as artifacts were picked out. Through pétrographie and geochemical analysis rhese samples were compared with typical sources from oustanding Paso Limay quarry-factory and evaluared their regional distriburion. The purpose of this work is to expose the methodology to obtain detailed characterization of this important lithic source marter.

  1. Geological fieldwork in the Libyan Sahara: A multidisciplinary approach

    Science.gov (United States)

    Meinhold, Guido; Whitham, Andrew; Howard, James P.; Morton, Andrew; Abutarruma, Yousef; Bergig, Khaled; Elgadry, Mohamed; Le Heron, Daniel P.; Paris, Florentin; Thusu, Bindra

    2010-05-01

    Libya is one of the most hydrocarbon-rich countries in the world. Its large oil and gas reserves make it attractive to international oil and gas companies, which provide the impetus for field-based research in the Libyan Sahara. North Africa is made up of several enormous intracratonic basins, two of which are found in southern Libya: the Murzuq Basin, in the southwest, and the Kufra Basin, in the southeast, separated by the Tibesti Massif. Both basins are filled with Palaeozoic and Mesozoic clastic sedimentary rocks reaching up to 5 km in thickness. These basins developed from the Cambrian onwards following an earlier period of orogenesis (the Panafrican Orogeny) in the Neoproterozoic. Precambrian metasediments and granitoids are unconformably overlain by Cambrian and Ordovician conglomerates and sandstones. They show a transitional environment from continental to shallow marine. Skolithos-bearing sandstone is common in Ordovician strata. By the Late Ordovician, ice masses had developed across West Gondwana. Upon melting of the ice sheets in the latest Hirnantian, large volumes of melt water and sediment were released that were transported to the periphery of Gondwana. In Libya, these sediments are predominantly highly mature sandstones, which, in many places, are excellent hydrocarbon reservoirs. Polished and striated surfaces in these sandstones clearly point to their glaciogenic origin. Following Late Ordovician deglaciation, black shale deposition occurred in the Silurian. Some of the shales are characterised by high values of total organic carbon (TOC). These shales are commonly referred to as ‘hot shales' due to their associated high uranium content, and are the major source rock for Early Palaeozoic-sourced hydrocarbons in North Africa. Late Ordovician glaciogenic sediments and the Early Silurian ‘hot shales' are therefore the main focus of geological research in the Libyan Sahara. Fluvial conglomerates and sandstones of Devonian age unconformably

  2. Low 60Fe Abundance in Semarkona and Sahara 99555

    Science.gov (United States)

    Tang, Haolan; Dauphas, Nicolas

    2015-03-01

    Iron-60 (t1/2 = 2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of 60Fe(60Fe/56Fe ≈ 4 × 10-7) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range of meteoritic materials, including chondrules, showed that 60Fe was present in the early Solar System at a much lower level (60Fe/56Fe ≈ 10-8). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ˜2× chondritic. Here, we show that the initial 60Fe/56Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ˜24× chondritic is (5.39 ± 3.27) × 10-9. We also establish the initial 60Fe/56Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be (1.97 ± 0.77) × 10-9. These results demonstrate that the initial abundance of 60Fe at Solar System birth was low, corresponding to an initial 60Fe/56Fe ratio of (1.01 ± 0.27) × 10-8.

  3. LOW {sup 60}FE ABUNDANCE IN SEMARKONA AND SAHARA 99555

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Haolan; Dauphas, Nicolas, E-mail: haolantang@ucla.edu [Origins Lab, Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago IL 60637 (United States)

    2015-03-20

    Iron-60 (t{sub 1/2} = 2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of {sup 60}Fe({sup 60}Fe/{sup 56}Fe ≈ 4 × 10{sup −7}) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) measurements of a wide range of meteoritic materials, including chondrules, showed that {sup 60}Fe was present in the early Solar System at a much lower level ({sup 60}Fe/{sup 56}Fe ≈ 10{sup −8}). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ∼2× chondritic. Here, we show that the initial {sup 60}Fe/{sup 56}Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ∼24× chondritic is (5.39 ± 3.27) × 10{sup −9}. We also establish the initial {sup 60}Fe/{sup 56}Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be (1.97 ± 0.77) × 10{sup −9}. These results demonstrate that the initial abundance of {sup 60}Fe at Solar System birth was low, corresponding to an initial {sup 60}Fe/{sup 56}Fe ratio of (1.01 ± 0.27) × 10{sup −8}.

  4. Optimal power flow using the league championship algorithm: A case study of the Algerian power system

    International Nuclear Information System (INIS)

    Bouchekara, H.R.E.H.; Abido, M.A.; Chaib, A.E.; Mehasni, R.

    2014-01-01

    Highlights: • Optimal power flow. • Reducing electrical energy loss. • Saving electrical energy. • Optimal operation. - Abstract: A new efficient optimization method, called the League Championship Algorithm (LCA) is proposed in this paper for solving the optimal power flow problem. This method is inspired by the competition of sport teams in an artificial sport league for several weeks and over a number of seasons. The proposed method has been applied to the Algerian power system network for different objectives. Furthermore, in order to assess the effectiveness of the proposed LCA method the obtained results using this method have been compared to those obtained using other methods reported in the literature. The obtained results and the comparison with other techniques indicate that the league championship algorithm provides effective and high-quality solution when solving the optimal power flow problem

  5. [Handling of cytostatics in oncology wards of an Algerian university hospital].

    Science.gov (United States)

    Bouaziz, Nadia Tigha; Tourab, Djamel; Nezzal, Abdelmalek

    2017-04-27

    Introduction: A study was conducted in the oncology wards of an Algerian university hospital in order to analyse cytostatic handling conditions. Materials and methods: Working conditions were evaluated in 2014 and then re-evaluated after opening of the cancer centre in 2015, using validated tools: professional questionnaire, ward monograph support and oncology ward audit support. The results were compared to clinical practice guidelines and oncology wards were classified according to the percentage compliance: non-compliance (handling conditions was observed in 2015, concerning personnel training, recruitment of clinical pathologists and pharmacists, floorspace and hygiene of premises, storage of cytostatic agents and individual and collective protection equipment. Conclusion: In the light of this study, it appears relevant to improve cytostatic handling conditions by setting up a medical and environmental surveillance programme with the participation of all prevention personnel.

  6. Open Innovation: A New Mechanism For Adoption Of Organizational Innovation Empirical Evidence From Algerian Companies

    Directory of Open Access Journals (Sweden)

    Khayra Aichouche

    2016-06-01

    Full Text Available  The aim of this paper is to analyze the relationship between the openness degree of companies and organizational innovation. The openness degree is defined as the use of purposive inflows and outflows of knowledge to accelerate internal Innovation, and to expend markets for external use of innovation (Chesbrough, 2006. The research utilizes causality models and suggests a conceptual schema subsequent to a comprehensive analysis of the literature linked to open innovation field. A sample of 120 managers and employees of Algerian pharmaceutical company is used. The SEM is used to analyze and approve the proposal of the conceptual schema. Results of the empirical research show that open innovation is positively and significantly related to organizational innovation, on the other hand, these results indicate that there is a positive and significant impact of organizational innovation on organizational performance.

  7. A first-of-its-kind visit for 12 Algerian professors and students

    CERN Multimedia

    Kate Shaw

    2014-01-01

    The Cirta-Science competition is open to 51 high schools in the Constantine region of Algeria. This year the prize for the winners was a historic visit to see the place where the Higgs boson was discovered and meet scientists working at CERN, some of whom are from Algeria.   The group was composed of two physics professors from Constantine University and ten students from the Algerian Sirius Astronomy Association, including three laureates of the Cirta-Science scientific competition. Abdelhak Djouadi, a theoretical physicist at CERN from Algeria, was invited to announce the winners of this prestigious competition. The group of visitors had a very tight schedule, including a number of meetings with CERN scientists and visits to the SC, ATLAS and CMS. Since 2008 Algeria has had an international cooperation agreement with CERN, and in May 2014 a Protocol was signed which will involve the ATLAS and ISOLDE experiments.

  8. Characterization and Antioxidant Properties of Six Algerian Propolis Extracts: Ethyl Acetate Extracts Inhibit Myeloperoxidase Activity

    Directory of Open Access Journals (Sweden)

    Yasmina Mokhtaria Boufadi

    2014-02-01

    Full Text Available Because propolis contains many types of antioxidant compounds such as polyphenols and flavonoids, it can be useful in preventing oxidative damages. Ethyl acetate extracts of propolis from several Algerian regions show high activity by scavenging free radicals, preventing lipid peroxidation and inhibiting myeloperoxidase (MPO. By fractioning and assaying ethyl acetate extracts, it was observed that both polyphenols and flavonoids contribute to these activities. A correlation was observed between the polyphenol content and the MPO inhibition. However, it seems that kaempferol, a flavonoid, contributes mainly to the MPO inhibition. This molecule is in a high amount in the ethyl acetate extract and demonstrates the best efficiency towards the enzyme with an inhibiting concentration at 50% of 4 ± 2 µM.

  9. Antioxidant and Biological Activities of Proteinaceous Extract from Algerian Glycine max Plant.

    Science.gov (United States)

    Soussi, Nassima; Moulay, Saad; Bachari, Khaldoun; Benmiri, Yamina

    2017-01-01

    Glycine max is commonly used in Algeria for treatment of anemia deficiency and osteoporosis, it ranks first in terms of vegetal proteins. The experiment was aimed at characterizing the proteinaceous Glycine max extract and evaluating its antioxidant, biological and hematological potential. Extraction of proteinaceous materials from Glycine max plant was undertaken using water and n-hexane as extracting media. The isolation of proteins from the crude materials was done, providing the use of ammonium sulfate. The Glycine max proteins were characterized by UV-visible and FT-IR spectroscopy and analyzed by SEM micrograph and x-ray diffraction (XRD). Rheological parameters G' and G'' were assessed. The isolated proteins were tested for their antioxidant, antimicrobial and hemagglutination activities. There was a gelling effect of the protein extract which can be used as an alternative in principally made vaccines with its microbiological and antifungal activities. The proteinaceous extract from Algerian Glycine max would have a potential use in biomedical application.

  10. APPLICATION OF STIMULUS & RESPONSE MODEL TO IMPULSE BUYING BEHAVIOR OF ALGERIAN CONSUMERS

    Directory of Open Access Journals (Sweden)

    Amel Graa

    2012-02-01

    Full Text Available This paper investigates the influence of situational factors on the impulse buying behavior usinga Mehrabian and Russell's (1974 framework (Stimulus & response model. The results suggest thata consumer's emotions can be a mediating factor in the impulse purchase process. In this study, weidentify and explore how situational factors and emotional states may influence various dimensionsof impulse purchase behavior of Algerian shoppers. By tapping the responses of 687 consumers inthe area of Algeria’ west, we obtain that there is a positive relationship between independent anddependent variables.According to the results, pleasure was associated with design, whereas arousal was associatedwith perception of crowding, but dominance was linked to time spent in the store. Retailers can takethese findings to maintain trained their employees and provide adequate signs and best environmentwhenever some relocation of products took place.

  11. Social Media Use in Algerian Universities: University of Constantine 2 Case Study

    Directory of Open Access Journals (Sweden)

    Behdja Boumarafi

    2015-08-01

    Full Text Available Social media technologies initially used for socializing, and entertainment have in recent years expanded their reaches into learning activities providing an open space for students’ engagement. The positive effect of such technologies on pedagogy is to make learning applicable to the cyber environment to achieve independent and collaborative learning. Students learn to communicate and collaborate electronically. This requires rethinking the way pedagogical activities are carried out to develop synergistic learning relationships to create the best learning model in line with this new educational paradigm. This paper investigates Algerian students’ engagement to understand the developmental implications of academic achievement. The author seeks to advance the use of instructional interactions in two ways: i: enhancing the academic validity of social networking, ii: making the link to students’ collaborative learning explicit. Data is collected from 300 students. Findings show that social media are used for a multitude of purposes and Facebook is most popular.

  12. [HLA-DRB1 and HLA-DQB1 polymorphism in Algerians from Algiers].

    Science.gov (United States)

    Reviron, D; André, M; Cantaloube, J F; Biagini, P; Chicheportiche, C; Mercier, P

    1993-12-01

    The polymorphism of HLA-DRB1 and HLA-DQB1 genes in 100 unrelated Algerians from Alger was investigated using PCR amplification and oligonucleotide typing. Compared to western Europeans, this population shows a higher haplotypic frequency of HLA DRB1*03-DQB1*0201 (21.5%) and a lower haplotypic frequency of DRB1*0101-DQB1*0501 (2%). Two unexpected haplotypes are observed: DRB1*07-DQB1*0301 and DRB1*0406-DQB1*0402. DRB1*0402 is the most common subtype in the DRB1*04 group. Furthermore, we detected a rare DQB1*0305 allele, only found in a Sardinian subject until today.

  13. The Algerian gas is on the verge of changing its religion

    International Nuclear Information System (INIS)

    El Kadi, I.

    2009-01-01

    Algeria has not forged, during the years 2000, a natural gas 'diplomacy' comparable - by far - to the Russian one. Three obstacles were on its way: first, proved reserves are six time less than those of the top world producer; secondly, its maneuver margin has been for a long time reduced by long term supply contracts (to South Europe essentially); thirdly, Algeria experienced a great political difficulty to define a strategy that could be adapted to the new world context of rarefied energy sources, a context that is clearer since 2003-2004. The author explains the changes that have happened within these three constraint lines since 2008. He notably comments the geopolitical incidence of the end of the long term sale contracts, the role of LNG in the global energy mix, and analyses the Algerian gas production perspectives and the possibility of an agreement between gas producing countries

  14. The blurred boundaries of political violence in the Sahel-Sahara

    DEFF Research Database (Denmark)

    Walther, Olivier

    2017-01-01

    The Sahel and the Sahara are faced with exceptional political instability involving a combination of rebellions, jihadist insurgencies, coups d’état, protest movements and illegal trafficking. Analysis of the outbreaks of violence reveals that the region is not just the victim of an escalation...... of wars and conflicts that marked the 20th century. The Sahel-Sahara has also become the setting of a globalised security environment, in which boundaries between what is local and global, domestic and international, military and civilian, politics and identity are blurred....

  15. Preliminary Examination of Sahara 99555: Mineralogy and Experimental Studies of a New Angrite

    Science.gov (United States)

    Mikouchi, T.; McKay, G.; Le, L.; Mittlefehldt, D. W.

    2000-01-01

    A 2710 g meteorite, Sahara 99555 (Sah99), was recently recovered from the Sahara and reported to be the 5th angrite. It is the largest angrite ever found and may offer useful information to better understand the unusual petrogeneses of this rare achondrite group. It may also allow us to examine the chronological record of igneous activity in the very early solar system. We obtained a 2.6 g chip of Sah99 and here present a preliminary report of its petrology and mineralogy in conjunction with a crystallization experiment on an analogue composition.

  16. First images of the crustal structure across the central Algerian margin, off Tipaza (West Algiers) from deep penetrating seismic data: new information to constrain the opening of the Algerian basin

    Science.gov (United States)

    Leprêtre, A.; Deverchere, J.; Klingelhoefer, F.; Graindorge, D.; Schnurle, P.; Yelles, K.; Bracene, R.

    2011-12-01

    The origin of the Algerian margin remains one of the key questions still unresolved in the Western Mediterranean sea. This is related to the unknown nature and kinematics of this Neogene basin. Whereas the westernmost margin is generally assumed to have been shaped as a STEP-fault (Subduction-Transform Edge Propagator, transcurrent) margin by the westward displacement of the Alboran block, the central Algerian margin is believed to have involved a NW-SE basin opening related to a southward slab rollback. This work sheds insight on this issue, using data acquired in the context of the Algerian-French program SPIRAL (Sismique Profonde et Investigation Régionale en Algérie): a cruise conducted on the 'R/V L'Atalante' in October-November 2009. It has provided 5 new combined onshore-offshore wide-angle seismic profiles and an extensive multi-channel seismic dataset spread along the margin, from Oran to Annaba. In this work, the available structural information on the ~N-S wide-angle transect of Tipaza is presented, where the margin broadens due to the presence of a bathymetric high (the Khayr-Al-Din bank) which is assumed to represent a remaining titled block of the passive margin. Along the transect, 39 OBS and 13 landstations recorded 751 low frequency airgun shots. Travel-time tomography and forward modelling were computed using the software developed by Zelt and Barton (1998) and Zelt and Smith (1992), to obtain the velocity structure in the region. A set of multi-channel seismic reflection profiles including two coincident profiles with the wide-angle data allows a combined interpretation and extend the deep structure in the Bou Ismail Bay. MCS data outline the sedimentary sequence filling the Algerian basin depicting an intensive salt tectonic associated with the Messinan Salinity Crisis and allowing to image locally below the salt layer. The deep penetrating data SPIRAL allow to image the sedimentary sequence in the Algerian basin off Tipaza (West Algiers) and

  17. Caries-related factors and bacterial composition of supragingival plaques in caries free and caries active Algerian adults

    OpenAIRE

    Amina Hoceini; Nihel Klouche Khelil; Ilhem Ben-Yelles; Amine Mesli; Sara Ziouani; Lotfi Ghellai; Nadia Aissaoui; Fatima Nas; Mounia Arab

    2016-01-01

    Objective: To compare oral hygiene practices, education and social background, food intake and oral malodor of Algerian adults suffering from dental caries with normal controls, and to determine and compare the bacterial composition of the supragingival plaques from the above-mentioned groups. Methods: Participants completed a questionnaire and were clinically examined for dental caries using decayed, missing and filled teeth index according to the criteria laid down by the World Health Or...

  18. The U Pb systematics of angrite Sahara 99555

    Science.gov (United States)

    Amelin, Yuri

    2008-10-01

    Angrite Sahara 99555 (hereafter SAH), precisely dated by Baker et al. (Baker J., Bizzarro M., Wittig N., Connelly J. and Haack H. (2005) Early planetesimal melting from an age of 4.5662 Gyr for differentiated meteorites. Nature436, 1127-1131), has been proposed as a new reference point for the early Solar System timescale and for calculation of the revised minimum age of our Solar System. The Pb-Pb age of SAH of 4566.18 ± 0.14 Ma, reported by Baker et al., differs from the Pb-Pb age of D'Orbigny, another basaltic angrite, of 4564.42 ± 0.12 Ma (Amelin Y. (2008) U-Pb ages of angrites. Geochim. Cosmochim. Acta72, 221-232), despite the fact that the relative 53Mn- 53Cr and 182Hf- 182W ages of these meteorites are identical. Here I report U-Pb data for 21 whole rock and pyroxene fractions from SAH, analyzed using the same approach as D'Orbigny (Amelin, 2008). These fractions contain between 1.3 and 8.9 pg of total common Pb, slightly more than analytical blank. Measured 206Pb/ 204Pb ratios are between 625 and 2817 for D'Orbigny, blank-corrected 206Pb/ 204Pb ratios are between 1173 and 6675. Eight acid-washed whole rock fractions yielded an isochron age of 4564.86 ± 0.38 Ma, MSWD = 1.5. Data for pyroxene fractions plot mostly above the whole rock isochron, and do not form a linear array in 207Pb/ 206Pb vs. 204Pb/ 206Pb isochron coordinates. The 207Pb ∗/ 206Pb ∗ model dates of the pyroxene fractions vary from 4563.8 ± 0.3 to 4567.1 ± 0.5 Ma. The difference between whole rock and pyroxene U-Pb systematics may be a result of re-distribution of radiogenic Pb at a mineral grain scale several million years after crystallization. Complexities of Sm-Nd, Lu-Hf, and possibly 26Al- 26Mg mineral systematics of SAH, described previously, may be related to the same process that caused the re-distribution of radiogenic Pb. Disturbance of isotopic chronometers renders SAH an imperfect anchor for the early Solar System timescale. The problems with age determination revealed by

  19. Clinical, immunological and genetic features in eleven Algerian patients with major histocompatibility complex class II expression deficiency

    Directory of Open Access Journals (Sweden)

    Djidjik Réda

    2012-08-01

    Full Text Available Abstract Presenting processed antigens to CD4+ lymphocytes during the immune response involves major histocompatibility complex class II molecules. MHC class II genes transcription is regulated by four transcription factors: CIITA, RFXANK, RFX5 and RFXAP. Defects in these factors result in major histocompatibility complex class II expression deficiency, a primary combined immunodeficiency frequent in North Africa. Autosomal recessive mutations in the RFXANK gene have been reported as being the principal defect found in North African patients with this disorder. In this paper, we describe clinical, immunological and genetic features of 11 unrelated Algerian patients whose monocytes display a total absence of MHC class II molecules. They shared mainly the same clinical picture which included protracted diarrhoea and respiratory tract recurrent infections. Genetic analysis revealed that 9 of the 11 patients had the same RFXANK founder mutation, a 26 bp deletion (named I5E6-25_I5E6+1, also known as 752delG26. Immunological and genetic findings in our series may facilitate genetic counselling implementation for Algerian consanguineous families. Further studies need to be conducted to determine 752delG26 heterozygous mutation frequency in Algerian population.

  20. Clinical, immunological and genetic features in eleven Algerian patients with major histocompatibility complex class II expression deficiency.

    Science.gov (United States)

    Djidjik, Réda; Messaoudani, Nesrine; Tahiat, Azzedine; Meddour, Yanis; Chaib, Samia; Atek, Aziz; Khiari, Mohammed Elmokhtar; Benhalla, Nafissa Keltoum; Smati, Leila; Bensenouci, Abdelatif; Baghriche, Mourad; Ghaffor, Mohammed

    2012-08-03

    Presenting processed antigens to CD4+ lymphocytes during the immune response involves major histocompatibility complex class II molecules. MHC class II genes transcription is regulated by four transcription factors: CIITA, RFXANK, RFX5 and RFXAP. Defects in these factors result in major histocompatibility complex class II expression deficiency, a primary combined immunodeficiency frequent in North Africa. Autosomal recessive mutations in the RFXANK gene have been reported as being the principal defect found in North African patients with this disorder. In this paper, we describe clinical, immunological and genetic features of 11 unrelated Algerian patients whose monocytes display a total absence of MHC class II molecules. They shared mainly the same clinical picture which included protracted diarrhoea and respiratory tract recurrent infections. Genetic analysis revealed that 9 of the 11 patients had the same RFXANK founder mutation, a 26 bp deletion (named I5E6-25_I5E6+1, also known as 752delG26). Immunological and genetic findings in our series may facilitate genetic counselling implementation for Algerian consanguineous families. Further studies need to be conducted to determine 752delG26 heterozygous mutation frequency in Algerian population.

  1. The mental representation of singular and plural nouns in Algerian Arabic as revealed through auditory priming in agrammatic aphasic patients.

    Science.gov (United States)

    Mimouni, Z; Kehayia, E; Jarema, G

    1998-01-01

    Working within the theoretical framework of prosodic nonconcatenative morphology developed by McCarthy (1975) for Semitic languages, we addressed, in the present paper, the issues of lexical representation, morphological relatedness, and modes of access in Algerian Arabic--a dialect of Standard Arabic--in an auditory morphological priming experiment. More specifically, we investigated the process of word recognition of singular and plural nouns in the performance of 24 non-brain-damaged subjects and 2 Algerian-speaking agrammatic aphasics. Plurals in Arabic involve either suffixation as in the sound plural (e.g., lbas "dress"/lbasat "dresses"), or stem-internal changes as in the broken plurals (e.g., kursi "chair"/krasa "chairs"). Our findings reveal a differential processing of the two forms, indicating whole word access for broken plurals and decomposition into word and suffix for suffixed plurals. Further, the evidence suggests for Algerian Arabic an architecture of the lexicon reflecting a family-like organization which takes into account language-specific features.

  2. The deep Algerian margin structure revisited by the Algerian-French SPIRAL research program, stage 2 : Wide-ange seismic experiment

    Science.gov (United States)

    Klingelhoefer, Frauke; Yellès, Abdelkarim; Bracène, Rabah; Graindorge, David; Ouabadi, Aziouz; Schnürle, Philippe; Scientific Party, Spiral

    2010-05-01

    During the second leg of the Algerien - French SPIRAL (Sismique Profonde et Investigation Regionale du Nord de l'ALgerie) cruise conducted on the R/V Atalante in October and November 2009 an extensive wide-angle seismic data-set was acquired on 5 regional transects off Algeria, from Arzew bay to the west, to Annaba to the east. The profiles are between 80 and 180 km in length and around 40 ocean-bottom seismometers were deployed on each profile. A 8350 cu. inch tuned airgun array consisting of 10 Bolt airguns was used to generate of deep frequency to allow for a good penetration. All profiles were extended on land up to 150 km by land-stations to better constrain the structure of the margin and the nature of the ocean-continent transition zone. Coincident reflection seismic, gravity and magnetic data were acquired on all profiles during the first leg of the cruise. The resulting data quality is very good with deep penetrating arrivals on most of the instruments. Only on very few instruments a deep salt layer inhibits deeper penetration of the seismic energy. Two instruments were lost and all other yielded useful information on geophone and hydrophone channels. Instruments located close to the coast show arrivals from thick sedimentary layers. Instruments located on oceanic crust indicate a relatively thin crust overlying a mantle layer characterised by seismic velocities of 8 km/s. Forward and inverse modelling of the wide-angle seismic data will help constrain the deep structure of the margin, the nature of the crust and might help to constrain possible existence of a detached slab in the upper mantle. Integration of the wide-angle seismic data with multichannel seismic, gravity and magnetic data will enable us to better understand the tectonic history and the structure of the Algerian margin.

  3. SAHARA-J: Journal of Social Aspects of HIV/AIDS: Editorial Policies

    African Journals Online (AJOL)

    SAHARA Journal Mission Statement The journal publishes contributions in English and French from all fields of social aspects of HIV/AIDS (care, support, ... culture, faith-based approaches, evidence-based intervention, health communication, structural and environmental intervention, financing, policy, media, etc).

  4. Quality in primary health care services in sub-Sahara Africa: right or ...

    African Journals Online (AJOL)

    The Primary Health Care (PHC) system has been the foundation for the operation of the health system in most of Sub-Sahara Africa following the Alma Ata Declaration in 1978. Quality of care is an important determinant of health services utilization, and is a health outcome of public health importance. It is known that the ...

  5. Alternate non-stop migration strategies of pied flycatchers to cross the Sahara desert

    NARCIS (Netherlands)

    Ouwehand, Janne; Both, Christiaan

    Each year more than two billion songbirds cross the Sahara, but how they perform this formidable task is largely unknown. Using geolocation tracks from 27 pied flycatchers, a nocturnally migrating passerine, we show that most birds made diurnal flights in both autumn and spring. These diurnal

  6. SAHARA-J: Journal of Social Aspects of HIV/AIDS: An Open Access ...

    African Journals Online (AJOL)

    2013-10-04

    Oct 4, 2013 ... HIV and AIDS in Kakola location, Nyando District, Kisumu County, Kenya, SAHARA-J: Journal of Social Aspects of HIV/AIDS: An Open Access ... reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any .... Both experienced stigma, poverty, and a lack of basic care.

  7. Le Sahara marocain : désenclavement et développement durable

    Directory of Open Access Journals (Sweden)

    EL MAHJOUB CHMOURK

    2012-04-01

    Full Text Available The Moroccan Sahara: opening-up and sustainable development. The enclosing of the Moroccan Sahara results from the inversion and old situation. Indeed, during a very long time, the area was a way of passage, a platform in the south of Morocco. In testify the Tran-Saharan commercial routes, which were the main transportation routes back in time, like the goal of integration of the area in the country and compared to western Africa. It is with the economic crisis, and even a political crisis causing a fold on itself of this area until 1975.Since Sahara belongs to Morocco, it still profits a considerable public effort to carry out its opening-up and its economic insertion within the country. Massive investments carried out by the State give to the area the structuring which it missed. Which are the aspects of the Sahara development? Which role played the State in this development? The intervention of the State contributes to bring effective solutions to the problem of the opening-up of this surrounding space?

  8. SAHARA-J: Journal of Social Aspects of HIV/AIDS - Vol 9, No 2 (2012)

    African Journals Online (AJOL)

    SAHARA J Journal of Social Aspects of HIV/AIDS Research Alliance. ... The experiences of Batswana families regarding hospice care of AIDS patients in the Bophirima district, North West province, South Africa · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  9. SAHARA-J: Journal of Social Aspects of HIV/AIDS

    African Journals Online (AJOL)

    SAHARA-J: Journal of Social Aspects of HIV/AIDS. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 3, No 1 (2006) >. Log in or Register to get access to full text downloads.

  10. Zimbabwe's national AIDS levy: A case study | Bhat | SAHARA-J ...

    African Journals Online (AJOL)

    SAHARA-J: Journal of Social Aspects of HIV/AIDS. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 13, No 1 (2016) >. Log in or Register to get access to full text downloads.

  11. Sud du Sahara | Page 59 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    flexible layout. Sud du Sahara. There is ample evidence that addressing gender inequalities and empowering women are vital to meeting the challenges of improving food and nutrition security, and enabling poor rural people to overcome poverty. A central objective of the Canadian International Food Security Research ...

  12. Sud du Sahara | Page 272 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sud du Sahara. Read more about Decentralization, Local Politics and the Construction of Women's Citizenship (Uganda, Kenya and Tanzania) - Phase I. Langue English. Read more ... Read more about Monitoring Progress Toward the Information Society : Digital Divide Index. Langue English. Read more about Réforme ...

  13. SAHARA-J: Journal of Social Aspects of HIV/AIDS: An Open Access ...

    African Journals Online (AJOL)

    2013-05-30

    May 30, 2013 ... SAHARA-J: Journal of Social Aspects of HIV/AIDS: An. Open Access Journal ... disseminated to the public through mass media since the start of the epidemic in 1984 and AIDS cases in 1986 have played a significant role ..... discrimination affect self-esteem of PLHIV, which resulted in stress that in turn ...

  14. Hibiscus plant named `Sahara Sunset` U.S. Plant Patent 21,765

    Science.gov (United States)

    'Sahara Sunset' is a new and distinct cultivar of Hibiscus, botanically known as Hibiscus acetosella. The new Hibiscus was originated in Poplarville, Miss. and is a product of a mutation induction program. The parent of the present new cultivar is an unknown Hibiscus acetosella Wels. Ex Hiern seedli...

  15. Green Sahara impact on mid-latitudes during mid-Holocene

    Science.gov (United States)

    Gaetani, Marco; Messori, Gabriele; Pausata, Francesco S. R.; Zhang, Qiong

    2017-04-01

    In the mid-Holocene (6 kyr before present), North Africa was characterised by a vegetated Sahara and a stronger summer monsoon, resulting in a wetter climate. These conditions, induced by the different Earth's orbital parameters, and maintained by the precipitation-vegetation feedback, were associated with a substantial change of the regional atmospheric dynamics, with influences extending across the global Tropics and beyond. In this study, we explore the mid-latitude response to the vegetated Sahara in the mid-Holocene. We use the EC-Earth climate model to simulate the North African environment during mid-Holocene, i.e. extensive vegetation over the Sahara, and a consequent reduced dust emission. Vegetation and dust reduction are prescribed both in combination and in isolation, to determine the specific responses to the individual forcings. A significant response at mid-latitudes is simulated during boreal summer, when the precipitation-vegetation feedback is maximum in the Sahara. Results show increased precipitation over Mediterranean and Middle East, and warm anomalies across western Europe. This response is associated with the modification of the atmospheric circulation in the Euro-Atlantic sector. Specifically, the intensification of the subtropical jetstream favours precipitation across the Middle East, while a positive anomaly in the North Atlantic Oscillation leads the warming further west. These results suggest important implications for the understanding of future climate scenarios in the region, since a number of simulations project wetter conditions in North Africa.

  16. Unravelling biodiversity, evolution and threats to conservation in the Sahara-Sahel.

    Science.gov (United States)

    Brito, José C; Godinho, Raquel; Martínez-Freiría, Fernando; Pleguezuelos, Juan M; Rebelo, Hugo; Santos, Xavier; Vale, Cândida G; Velo-Antón, Guillermo; Boratyński, Zbyszek; Carvalho, Sílvia B; Ferreira, Sónia; Gonçalves, Duarte V; Silva, Teresa L; Tarroso, Pedro; Campos, João C; Leite, João V; Nogueira, Joana; Alvares, Francisco; Sillero, Neftalí; Sow, Andack S; Fahd, Soumia; Crochet, Pierre-André; Carranza, Salvador

    2014-02-01

    Deserts and arid regions are generally perceived as bare and rather homogeneous areas of low diversity. The Sahara is the largest warm desert in the world and together with the arid Sahel displays high topographical and climatic heterogeneity, and has experienced recent and strong climatic oscillations that have greatly shifted biodiversity distribution and community composition. The large size, remoteness and long-term political instability of the Sahara-Sahel, have limited knowledge on its biodiversity. However, over the last decade, there have been an increasing number of published scientific studies based on modern geomatic and molecular tools, and broad sampling of taxa of these regions. This review tracks trends in knowledge about biodiversity patterns, processes and threats across the Sahara-Sahel, and anticipates needs for biodiversity research and conservation. Recent studies are changing completely the perception of regional biodiversity patterns. Instead of relatively low species diversity with distribution covering most of the region, studies now suggest a high rate of endemism and larger number of species, with much narrower and fragmented ranges, frequently limited to micro-hotspots of biodiversity. Molecular-based studies are also unravelling cryptic diversity associated with mountains, which together with recent distribution atlases, allows identifying integrative biogeographic patterns in biodiversity distribution. Mapping of multivariate environmental variation (at 1 km × 1 km resolution) of the region illustrates main biogeographical features of the Sahara-Sahel and supports recently hypothesised dispersal corridors and refugia. Micro-scale water-features present mostly in mountains have been associated with local biodiversity hotspots. However, the distribution of available data on vertebrates highlights current knowledge gaps that still apply to a large proportion of the Sahara-Sahel. Current research is providing insights into key

  17. Lakeside cemeteries in the Sahara: 5000 years of holocene population and environmental change.

    Directory of Open Access Journals (Sweden)

    Paul C Sereno

    Full Text Available BACKGROUND: Approximately two hundred human burials were discovered on the edge of a paleolake in Niger that provide a uniquely preserved record of human occupation in the Sahara during the Holocene ( approximately 8000 B.C.E. to the present. Called Gobero, this suite of closely spaced sites chronicles the rapid pace of biosocial change in the southern Sahara in response to severe climatic fluctuation. METHODOLOGY/PRINCIPAL FINDINGS: Two main occupational phases are identified that correspond with humid intervals in the early and mid-Holocene, based on 78 direct AMS radiocarbon dates on human remains, fauna and artifacts, as well as 9 OSL dates on paleodune sand. The older occupants have craniofacial dimensions that demonstrate similarities with mid-Holocene occupants of the southern Sahara and Late Pleistocene to early Holocene inhabitants of the Maghreb. Their hyperflexed burials compose the earliest cemetery in the Sahara dating to approximately 7500 B.C.E. These early occupants abandon the area under arid conditions and, when humid conditions return approximately 4600 B.C.E., are replaced by a more gracile people with elaborated grave goods including animal bone and ivory ornaments. CONCLUSIONS/SIGNIFICANCE: The principal significance of Gobero lies in its extraordinary human, faunal, and archaeological record, from which we conclude the following: The early Holocene occupants at Gobero (7700-6200 B.C.E. were largely sedentary hunter-fisher-gatherers with lakeside funerary sites that include the earliest recorded cemetery in the Sahara.Principal components analysis of craniometric variables closely allies the early Holocene occupants at Gobero with a skeletally robust, trans-Saharan assemblage of Late Pleistocene to mid-Holocene human populations from the Maghreb and southern Sahara.Gobero was abandoned during a period of severe aridification possibly as long as one millennium (6200-5200 B.C.E.More gracile humans arrived in the mid

  18. Síntesis de los estudios sobre moluscos continentales neógenos del sector septentrional de la Depresión de Teruel: período 1775-1998

    Directory of Open Access Journals (Sweden)

    Robles, F.

    2006-12-01

    Full Text Available The relevant information on the fossil record of the Neogene molluscs of the north of the Teruel Basin in the period between the years 1775-1998 is compiled and analyzed. First, the total number of different taxa mentioned in every paper is counted, second only the number of specific references is counted. The last references are divided into three categories called: new references, new species and repeated references. Apart from the information contained in every paper, the number of taxa contemplated, and the typology of the specific references, it is proposed a classification of the studies on neogene molluscs of this area in six stages: first (1775-1849, second (1849-1910, third (1910-1936, fourth (1936-1962, fifth (1962-1991 and sixth (1991-1998.Se recopila y analiza la información que se considera más relevante y se encuentra contenida en los estudios realizados sobre el registro fósil de los moluscos neógenos del sector septentrional de la Depresión de Teruel en el período comprendido entre los años 1775 y 1998. Se contabilizan, por una parte, el número total de taxones diferentes mencionados en cada trabajo y, por otra, sólo el número de citas efectuadas a nivel de especie en cada uno de ellos. Estas últimas se organizan en tres categorías que reciben el nombre de citas nuevas, especies nuevas y citas repetidas. Se propone, a partir de la información contenida en cada trabajo, el número de taxones contemplados, y la tipología de sus citas específicas, una clasificación de los estudios sobre moluscos neógenos de esta área en seis etapas: primera (1775-1849, segunda (1849-1910, tercera (1910 1936, cuarta (1936-1962, quinta (1962-1991 y sexta (1991-1998.

  19. Review: Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara (2012 Buchbesprechung: Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara (2012

    Directory of Open Access Journals (Sweden)

    Laurence Marfaing

    2013-01-01

    Full Text Available Review of the monograph:Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara, 2 volumes, Berlin/Tübingen: Verlag Hans Schiler, 2012, ISBN 9783899303674, xiv + 1,438 pagesBesprechung der Monographie:Steffen Wippel, Wirtschaft, Politik und Raum: Territoriale und regionale Prozesse in der westlichen Sahara, 2 Bände, Berlin/Tübingen: Verlag Hans Schiler, 2012, ISBN 9783899303674, xiv + 1,438 Seiten

  20. Classification of some Meteorites from Tunisia and Morocco: On the way to Estimate the Flux of Meteorites in Sahara

    Science.gov (United States)

    Aboulahris, M.; Chennaoui Aoudjehane, H.; Rochette, P.; Gattacceca, J.; Laridhi Ouazaa, N.; Bartoschewitz, R.; Buhl, S.

    2014-09-01

    Estimation of flux of meteorites on Earth gives us an idea about the history of our planet. This estimation can be performed in large desert area, including the Sahara where many meteorites has been accumulated during the time.

  1. Technological Aptitude and Applications of Leuconostoc mesenteroides Bioactive Strains Isolated from Algerian Raw Camel Milk

    Science.gov (United States)

    Benmechernene, Zineb; Chentouf, Hanane Fatma; Yahia, Bellil; Fatima, Ghazi; Quintela-Baluja, Marcos; Calo-Mata, Pilar; Barros-Velázquez, Jorge

    2013-01-01

    Two strains (B7 and Z8) of the Leuconostoc mesenteroides subspecies mesenteroides that were isolated from Algerian camel milk from an initial pool of 13 strains and demonstrated a high ability to inhibit the growth of Listeria spp. were selected and characterised at the phenotypic and genotypic levels. Probiotic profiling and inhibition spectra against food borne pathogens in mixed cultures were also investigated. The bacteriocin produced by L. mesenteroides strain B7 was identified as leucocin B by specific PCR. In vitro studies demonstrated that both Leuconostoc mesenteroides strains exhibited a marked probiotic profile, showing high survival at low pH (2-3 and 4) in the presence of 0.5%, 1%, and 2% of bile salts and at pH 3 in the presence of 3 mg/mL pepsin. Susceptibility testing against antimicrobial agents was also performed for both strains. When tested in a mixed culture with Listeria innocua, Listeria ivanovii, or Staphylococcus aureus, strain B7 reduced the numbers of these species by 1.87, 1.78, and 1.38 log units, respectively. Consequently, these two strains were found to possess good probiotic properties in vitro and a high capacity for Listeria spp. inhibition in mixed cultures. Therefore, these strains have a favourable technological aptitude and a potential application as novel probiotic starters. PMID:24392451

  2. Lactobacilli isolated from Algerian goat's milk as adjunct culture in dairy products

    Directory of Open Access Journals (Sweden)

    Ahmed Marroki

    2014-06-01

    Full Text Available In this study, nineteen Lactobacillus isolated from Algerian goat's milk, 13 belonging to L. plantarum, three to L. pentosus, two to L. rhamnosus and one to L. fermentum, were examined in vitro in order to be used as adjunct culture in dairy products. The strains were tested for their proteolytic activity, sensory and safety properties. Strains LbMS16 and LbMS21 L. plantarum and LbMF25 L. rhamnosus presented the highest proteolytic activity. All the tested lactobacilli were able to grow on MRS agar containing 0.5 and 1% (W/V of oxgall, whereas none produced biogenic amine (BA from the four tested amino acids and were resistant to pH 2.0 and 3.0, but some strains were able to grow at pH 3.5. None of examined strains were β-haemolytic when grown in hors blood agar. Result of antibiotic resistance showed that all the strains were susceptible to penicillin, erythromycin and resistant to vancomycin. Diacetyl production was observed for two strains of L. plantarum and one of L. rhamnosus. Most of strains were able to produce pleasant flavours in fermented milk and gave a good acceptance. According to these results, the strains LbMS16, LbMS21and LbMF25 could be good candidates to be used as adjunct culture, playing a probiotic role in dairy products manufacture in Algeria.

  3. Economic evaluation of nuclear seawater desalination in an Algerian site: La Macta

    International Nuclear Information System (INIS)

    Belkaid, Abderrahmane; Amzert, Sid Ahmed; Arbaoui, Fahd; Bouaichaoui, Youcef

    2010-01-01

    As the needs for fresh water and electricity increases rapidly in Algeria, the Algerian authorities launched a study to assess the potentialities of the introduction of nuclear energy for the production of electricity and potable water. This study which started in 2007, is held under the framework of an IAEA Project untitled: 'techno-economic feasibility study of seawater desalination using nuclear energy' and its objective is to provide a document which will be used to support the government's decision to introduce the nuclear desalination in Algeria. To that end, one site has been selected to host nuclear desalination plant. This site is located in North West region of the country. In this study, we present the results achieved under this project and which corresponds to the economical evaluation of coupling several nuclear reactors: GT-MHR, PBMR, AP1000 and PWR900, with two desalination processes MED and RO. The results are compared with those obtained with fossil energy sources: Natural Gas Turbine and Natural Gas Combined Cycle. (author)

  4. Porosity Estimation By Artificial Neural Networks Inversion . Application to Algerian South Field

    Science.gov (United States)

    Eladj, Said; Aliouane, Leila; Ouadfeul, Sid-Ali

    2017-04-01

    One of the main geophysicist's current challenge is the discovery and the study of stratigraphic traps, this last is a difficult task and requires a very fine analysis of the seismic data. The seismic data inversion allows obtaining lithological and stratigraphic information for the reservoir characterization . However, when solving the inverse problem we encounter difficult problems such as: Non-existence and non-uniqueness of the solution add to this the instability of the processing algorithm. Therefore, uncertainties in the data and the non-linearity of the relationship between the data and the parameters must be taken seriously. In this case, the artificial intelligence techniques such as Artificial Neural Networks(ANN) is used to resolve this ambiguity, this can be done by integrating different physical properties data which requires a supervised learning methods. In this work, we invert the acoustic impedance 3D seismic cube using the colored inversion method, then, the introduction of the acoustic impedance volume resulting from the first step as an input of based model inversion method allows to calculate the Porosity volume using the Multilayer Perceptron Artificial Neural Network. Application to an Algerian South hydrocarbon field clearly demonstrate the power of the proposed processing technique to predict the porosity for seismic data, obtained results can be used for reserves estimation, permeability prediction, recovery factor and reservoir monitoring. Keywords: Artificial Neural Networks, inversion, non-uniqueness , nonlinear, 3D porosity volume, reservoir characterization .

  5. Technological Aptitude and Applications of Leuconostoc mesenteroides Bioactive Strains Isolated from Algerian Raw Camel Milk

    Directory of Open Access Journals (Sweden)

    Zineb Benmechernene

    2013-01-01

    Full Text Available Two strains (B7 and Z8 of the Leuconostoc mesenteroides subspecies mesenteroides that were isolated from Algerian camel milk from an initial pool of 13 strains and demonstrated a high ability to inhibit the growth of Listeria spp. were selected and characterised at the phenotypic and genotypic levels. Probiotic profiling and inhibition spectra against food borne pathogens in mixed cultures were also investigated. The bacteriocin produced by L. mesenteroides strain B7 was identified as leucocin B by specific PCR. In vitro studies demonstrated that both Leuconostoc mesenteroides strains exhibited a marked probiotic profile, showing high survival at low pH (2-3 and 4 in the presence of 0.5%, 1%, and 2% of bile salts and at pH 3 in the presence of 3 mg/mL pepsin. Susceptibility testing against antimicrobial agents was also performed for both strains. When tested in a mixed culture with Listeria innocua, Listeria ivanovii, or Staphylococcus aureus, strain B7 reduced the numbers of these species by 1.87, 1.78, and 1.38 log units, respectively. Consequently, these two strains were found to possess good probiotic properties in vitro and a high capacity for Listeria spp. inhibition in mixed cultures. Therefore, these strains have a favourable technological aptitude and a potential application as novel probiotic starters.

  6. Oral Fat Sensing and CD36 Gene Polymorphism in Algerian Lean and Obese Teenagers

    Directory of Open Access Journals (Sweden)

    Hadjer Daoudi

    2015-11-01

    Full Text Available Growing number of evidences have suggested that oral fat sensing, mediated by a glycoprotein CD36 (cluster of differentiation 36, plays a significant role in the development of obesity. Indeed, a decreased expression of CD36 in some obese subjects is associated with high dietary fat intake. In the present study, we examined whether an increase in body mass index (BMI is associated with altered oleic acid lingual detection thresholds and blood lipid profile in young Algerian teenagers (n = 165. The obese teenagers (n = 83; 14.01 ± 0.19 years; BMI z-score 2.67 ± 0.29 exhibited higher lingual detection threshold for oleic acid than lean participants (n = 82, 13.92 ± 0.23 years; BMI z-score 0.03 ± 0.0001. We also studied the association between rs1761667 polymorphism of CD36 gene and obesity. The AA and AG genotypes were more frequent in obese teenagers, whereas GG genotype was more common in lean participants. The A-allele frequency was higher in obese teenagers than that in lean children. We report that rs1761667 polymorphism of CD36 gene and oro-gustatory thresholds for fat might play a significant role in the development of obesity in young teenagers.

  7. Technological aptitude and applications of Leuconostoc mesenteroides bioactive strains isolated from Algerian raw camel milk.

    Science.gov (United States)

    Benmechernene, Zineb; Chentouf, Hanane Fatma; Yahia, Bellil; Fatima, Ghazi; Quintela-Baluja, Marcos; Calo-Mata, Pilar; Barros-Velázquez, Jorge

    2013-01-01

    Two strains (B7 and Z8) of the Leuconostoc mesenteroides subspecies mesenteroides that were isolated from Algerian camel milk from an initial pool of 13 strains and demonstrated a high ability to inhibit the growth of Listeria spp. were selected and characterised at the phenotypic and genotypic levels. Probiotic profiling and inhibition spectra against food borne pathogens in mixed cultures were also investigated. The bacteriocin produced by L. mesenteroides strain B7 was identified as leucocin B by specific PCR. In vitro studies demonstrated that both Leuconostoc mesenteroides strains exhibited a marked probiotic profile, showing high survival at low pH (2-3 and 4) in the presence of 0.5%, 1%, and 2% of bile salts and at pH 3 in the presence of 3 mg/mL pepsin. Susceptibility testing against antimicrobial agents was also performed for both strains. When tested in a mixed culture with Listeria innocua, Listeria ivanovii, or Staphylococcus aureus, strain B7 reduced the numbers of these species by 1.87, 1.78, and 1.38 log units, respectively. Consequently, these two strains were found to possess good probiotic properties in vitro and a high capacity for Listeria spp. inhibition in mixed cultures. Therefore, these strains have a favourable technological aptitude and a potential application as novel probiotic starters.

  8. Algerian EFL University Teachers’ Attitudes towards Computer Assisted Language Learning: The Case of Djilali Liabes University

    Directory of Open Access Journals (Sweden)

    Miloud Bouchefra

    2017-04-01

    Full Text Available Computer Assisted Language Learning (CALL is still groping its way into Algerian English as a Foreign Language (EFL classroom, where Information Communications Technologies (ICTs are defined in terms of occasional use of computers and data projectors for material presentation in the classroom. Though major issues in the image of the lack of training and absence of facilities are clearly apparent, stakeholders’ attitudes are a decisive aspect that needs to be mapped out if we are to alter the current situation. Thus, the present work aims at investigating EFL university teachers’ attitudes towards CALL at Djilali Liabes University (western Algeria. The current work is a cross-sectional descriptive study that explores teachers’ attitudes across the three domains (affective, cognitive, and behavioural and investigates other related aspects that may help indicate teachers’ likelihood to adopt CALL in the future. The results are promising as the investigated population not only demonstrated a clearly positive attitude towards CALL but also manifested a number of signs that indicate their likelihood to adopt CALL in the future if circumstances are favourable.

  9. Comparative Study of Essential Oils Extracted from Algerian Myrtus communis L. Leaves Using Microwaves and Hydrodistillation

    Directory of Open Access Journals (Sweden)

    Karim S. Allaf

    2012-04-01

    Full Text Available Two different extraction methods were used for a comparative study of Algerian Myrtle leaf essential oils: solvent-free-microwave-extraction (SFME and conventional hydrodistillation (HD. Essential oils analyzed by GC and GC-MS presented 51 components constituting 97.71 and 97.39% of the total oils, respectively. Solvent-Free-Microwave-Extract Essential oils SFME-EO were richer in oxygenated compounds. Their major compounds were 1,8-cineole, followed by α-pinene as against α-pinene, followed by 1,8-cineole for HD. Their antimicrobial activity was investigated on 12 microorganisms. The antioxidant activities were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH• radical scavenging method. Generally, both essential oils showed high antimicrobial and weak antioxidant activities. Microstructure analyses were also undertaken on the solid residue of myrtle leaves by Scanning Electronic Microscopy (SEM; it showed that the SFME-cellular structure undergoes significant modifications compared to the conventional HD residual solid. Comparison between hydrodistillation and SFME presented numerous distinctions. Several advantages with SFME were observed: faster kinetics and higher efficiency with similar yields: 0.32% dry basis, in 30 min as against 180 min for HD.

  10. Comparative Study of Essential Oils Extracted from Algerian Myrtus communis L. Leaves Using Microwaves and Hydrodistillation

    Science.gov (United States)

    Berka-Zougali, Baya; Ferhat, Mohamed-Amine; Hassani, Aicha; Chemat, Farid; Allaf, Karim S.

    2012-01-01

    Two different extraction methods were used for a comparative study of Algerian Myrtle leaf essential oils: solvent-free-microwave-extraction (SFME) and conventional hydrodistillation (HD). Essential oils analyzed by GC and GC-MS presented 51 components constituting 97.71 and 97.39% of the total oils, respectively. Solvent-Free-Microwave-Extract Essential oils SFME-EO were richer in oxygenated compounds. Their major compounds were 1,8-cineole, followed by α-pinene as against α-pinene, followed by 1,8-cineole for HD. Their antimicrobial activity was investigated on 12 microorganisms. The antioxidant activities were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging method. Generally, both essential oils showed high antimicrobial and weak antioxidant activities. Microstructure analyses were also undertaken on the solid residue of myrtle leaves by Scanning Electronic Microscopy (SEM); it showed that the SFME-cellular structure undergoes significant modifications compared to the conventional HD residual solid. Comparison between hydrodistillation and SFME presented numerous distinctions. Several advantages with SFME were observed: faster kinetics and higher efficiency with similar yields: 0.32% dry basis, in 30 min as against 180 min for HD. PMID:22606003

  11. Repression and black holes in Laurent Mauvignier novel about Algerian War

    Directory of Open Access Journals (Sweden)

    Giacomo Raccis

    2015-12-01

    Full Text Available XXth century history obliged narrators to clash with events that was literally inexpressible, measuring the potential and the lack of literary means. Laurent Mauvignier made this confrontarion the centre of his poetics: from minimal, private tragedies to great, historical dramas, passing through the media mystification of absurd fait divers, his novels face the Evil problem and its representation in words. With Des hommes (2009, Mauvignier addresses his question to one of the most problematic repression object in historical French memory: Algerian War. Building a polyphonic novel, he deals with an event deeply characterized by silence (the veteran silence studied by Benjamin Stora and Andrea Brazzoduro and that has been manipulated by the institutional and mediatic vulgata. Infact, the narration shows how the amnesty of collective faults is based on the "order to say nothing" (overturning Foucault, first of all caused by the social load of an history that nobody wants. This paper aims at showing how Mauvignier's work, inspired by modernist novel and "nouveau roman" (Duras, Simon, resorts to literary experimentalism to "défamiliariser" this historical event using the tools of a fiction claiming the value of a "secondary experience" to redeem a piece of history refused by the public discourse.

  12. Algerian Immigrants to Spain: Study of Attitude to the Donation of Organs for Transplantation.

    Science.gov (United States)

    Ríos, A; Carrillo, J; López-Navas, A I; Martínez-Alarcón, L; Ayala, M A; Garrido, G; Sebastián, M J; Ramis, G; Hernández, A M; Ramírez, P; Parrilla, P

    2018-03-01

    Many Africans are emigrating to the European Economic Community from countries with little knowledge of transplantation. This population has not yet been studied. Analyze the attitude toward donation among the Algerian population living in Spain. We studied the population born in Algeria and residing in Spain, over 15 years old, and stratified by age and sex. Attitude was surveyed using a questionnaire of organ donation for transplantation ("PCID-DTO Ríos"). Support from African immigration associations was needed to advise on the location of potential respondents. The completion was anonymous and self-administered. Verbal consent was obtained to assist in the study. Of the 441 respondents, 27% (n = 119) were in favor of donation after death, 43% (n = 191) were against, and 30% (n = 131) were undecided. The variables associated with the attitude toward the donation were sex (P = .033), having offspring (P = .027), having commented on the subject of organ transplantation at the family level (P organ donation and transplantation (P transplant recipient or donor, with this subgroup having the most favorable attitude (68% vs 19%, P donation of their own organs. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Oral Fat Sensing and CD36 Gene Polymorphism in Algerian Lean and Obese Teenagers.

    Science.gov (United States)

    Daoudi, Hadjer; Plesník, Jiří; Sayed, Amira; Šerý, Omar; Rouabah, Abdelkader; Rouabah, Leila; Khan, Naim Akhtar

    2015-11-04

    Growing number of evidences have suggested that oral fat sensing, mediated by a glycoprotein CD36 (cluster of differentiation 36), plays a significant role in the development of obesity. Indeed, a decreased expression of CD36 in some obese subjects is associated with high dietary fat intake. In the present study, we examined whether an increase in body mass index (BMI) is associated with altered oleic acid lingual detection thresholds and blood lipid profile in young Algerian teenagers (n = 165). The obese teenagers (n = 83; 14.01 ± 0.19 years; BMI z-score 2.67 ± 0.29) exhibited higher lingual detection threshold for oleic acid than lean participants (n = 82, 13.92 ± 0.23 years; BMI z-score 0.03 ± 0.0001). We also studied the association between rs1761667 polymorphism of CD36 gene and obesity. The AA and AG genotypes were more frequent in obese teenagers, whereas GG genotype was more common in lean participants. The A-allele frequency was higher in obese teenagers than that in lean children. We report that rs1761667 polymorphism of CD36 gene and oro-gustatory thresholds for fat might play a significant role in the development of obesity in young teenagers.

  14. (Prérif Central, Maroc septentrional

    Directory of Open Access Journals (Sweden)

    Abdelghani Gartet

    2006-01-01

    Full Text Available El diapiro de sal de Tissa, situado en el Prerif central marroquí, afl ora en una zona de contacto estructural anormal donde la morfogénesis kárstica es muy activa. La solubilidad de las formaciones del complejo triásico es excesivamente fuerte. El macizo yesífero-salino representa un yacimiento de sal gema casi inagotable. Sin embargo, las aguas de Oued Lebène, en época de crecidas, socavan intensamente la base del macizo y terminan siendo afectadas por la contaminación química. La explotación de la cantera de sal, siendo tradicional, plantea numerosos problemas de planifi cación, a la vez que atenta severamente contra el medio ambiente (natural y urbano y contra la sociedad humana. Las medidas de defensa del medio ambiente adoptadas al respecto resultan por el momento insufi cientes dada la falta de una legislación práctica y rigurosa.

  15. Resource Geopolitics: Cold War Technologies, Global Fertilizers, and the Fate of Western Sahara.

    Science.gov (United States)

    Camprubí, Lino

    2015-07-01

    When, after years of geological and geophysical exploration, a phosphate mine was discovered at Bu-Craa in 1964, Western Sahara received renewed geopolitical attention. Several countries competing for the control of the world fertilizer market, including Morocco, Spain, France, and the United States, developed diverging strategies to gain control of the mineral. After intense negotiations revolving around the materiality of mining technologies and involving reserve estimations, sabotage, and flexing of diplomatic muscles, Morocco took over the Spanish colony in 1975. While this secured Morocco's place in the world market, it condemned the local population to exile and domination. This article explores three technological stages of the exploitation of phosphate in Western Sahara that underpin the geopolitical history. This perspective yields new visions of cold war technology and postcolonial markets.

  16. Tropical cyclone activity enhanced by Sahara greening and reduced dust emissions during the African Humid Period.

    Science.gov (United States)

    Pausata, Francesco S R; Emanuel, Kerry A; Chiacchio, Marc; Diro, Gulilat T; Zhang, Qiong; Sushama, Laxmi; Stager, J Curt; Donnelly, Jeffrey P

    2017-06-13

    Tropical cyclones (TCs) can have devastating socioeconomic impacts. Understanding the nature and causes of their variability is of paramount importance for society. However, historical records of TCs are too short to fully characterize such changes and paleo-sediment archives of Holocene TC activity are temporally and geographically sparse. Thus, it is of interest to apply physical modeling to understanding TC variability under different climate conditions. Here we investigate global TC activity during a warm climate state (mid-Holocene, 6,000 yBP) characterized by increased boreal summer insolation, a vegetated Sahara, and reduced dust emissions. We analyze a set of sensitivity experiments in which not only solar insolation changes are varied but also vegetation and dust concentrations. Our results show that the greening of the Sahara and reduced dust loadings lead to more favorable conditions for tropical cyclone development compared with the orbital forcing alone. In particular, the strengthening of the West African Monsoon induced by the Sahara greening triggers a change in atmospheric circulation that affects the entire tropics. Furthermore, whereas previous studies suggest lower TC activity despite stronger summer insolation and warmer sea surface temperature in the Northern Hemisphere, accounting for the Sahara greening and reduced dust concentrations leads instead to an increase of TC activity in both hemispheres, particularly over the Caribbean basin and East Coast of North America. Our study highlights the importance of regional changes in land cover and dust concentrations in affecting the potential intensity and genesis of past TCs and suggests that both factors may have appreciable influence on TC activity in a future warmer climate.

  17. The French experimentation at the underground nuclear testing site in the Sahara desert

    International Nuclear Information System (INIS)

    Gauvenet, Andre

    1970-01-01

    The present paper will be essentially an introduction to the technical exposes which will be delivered during the Las Vegas Meeting. The presentation is divided in two parts. The first part summarizes very briefly the experience that has been gained from the underground nuclear shots which took place in the Sahara desert from 1961 to 1966. in the second part, an idea is given of the studies at present carried on in France in the domain of peaceful applications of nuclear explosions

  18. Sud du Sahara | Page 78 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    flexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. La persistance de la pauvreté en Afrique subsaharienne, dans le contexte de progression rapide de la mondialisation et de la libéralisation des échanges commerciaux des deux dernières décennies, a suscité énormément de débats en ...

  19. Sud du Sahara | Page 65 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    flexible layoutflexible layoutflexible layoutflexible layoutflexible layout. Sud du Sahara. La persistance de la pauvreté en Afrique subsaharienne, dans le contexte de progression rapide de la mondialisation et de la libéralisation des échanges commerciaux des deux dernières décennies, a suscité énormément de débats en ...

  20. Sud du Sahara | Page 7 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    flexible layoutflexible layout. Sud du Sahara. Ce rapport fait fond sur les données recueillies dans le cadre d'une étude d'une durée de trois ans sur les attitudes, les perceptions et les intentions des entrepreneurs dans 10 pays d'Afrique subsaharienne menée par le projet et financée par le CRDI. Lancé en 1999, le projet ...

  1. Optimal power flow with environmental constraint using a fast successive linear programming algorithm: Application to the algerian power system

    International Nuclear Information System (INIS)

    Zehar, Khaled; Sayah, Samir

    2008-01-01

    Harmful ecological effects caused by the emission of gaseous pollutants like sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ), can be reduced by load adequate distribution between power plants. However, this leads to a noticeable increase in their operating cost. In order to eliminate this conflict, and to study the trade-off relation between fuel cost and emissions, an approach to solve this multiobjective environmental/economic load dispatch problem, based on an efficient successive linear programming technique is proposed. Simulation results on the Algerian 59-bus power system prove the efficiency of this method thus confirming its capacity to solve the environmental/economic power dispatch problem

  2. Wet phases in the Sahara/Sahel region and human migration patterns in North Africa.

    Science.gov (United States)

    Castañeda, Isla S; Mulitza, Stefan; Schefuss, Enno; Lopes dos Santos, Raquel A; Sinninghe Damsté, Jaap S; Schouten, Stefan

    2009-12-01

    The carbon isotopic composition of individual plant leaf waxes (a proxy for C(3) vs. C(4) vegetation) in a marine sediment core collected from beneath the plume of Sahara-derived dust in northwest Africa reveals three periods during the past 192,000 years when the central Sahara/Sahel contained C(3) plants (likely trees), indicating substantially wetter conditions than at present. Our data suggest that variability in the strength of Atlantic meridional overturning circulation (AMOC) is a main control on vegetation distribution in central North Africa, and we note expansions of C(3) vegetation during the African Humid Period (early Holocene) and within Marine Isotope Stage (MIS) 3 ( approximately 50-45 ka) and MIS 5 ( approximately 120-110 ka). The wet periods within MIS 3 and 5 coincide with major human migration events out of sub-Saharan Africa. Our results thus suggest that changes in AMOC influenced North African climate and, at times, contributed to amenable conditions in the central Sahara/Sahel, allowing humans to cross this otherwise inhospitable region.

  3. Low level jets over the Sahara: Results from 'Fennec: The Saharan Climate System'

    Science.gov (United States)

    Todd, Martin; Allen, Chris; Bechir, Mohammed; Cavazos, Carolina; Engelstaedter, Sebastian; Gandega, Abdoulaye; Hobby, Matt; Marsham, John; Parker, Doug; Saci, Azzedine; Washington, Richard

    2013-04-01

    Nocturnal Low level Jets (LLJs) are a commonplace feature of the atmosphere over West Africa including both the Sahelian and Saharan zones. Previous work has indicated LLJ activity in all seasons and within both the summertime southerly monsoon and the northerly Harmattan circulations. Notably, satellite-based analysis and the previously limited observational studies have indicated a major or even dominant role of LLJs in dust emission over the Sahara. Other work (including papers in this session) has also indicated a substantial LLJs play an important role in the heat and moisture budgets of the region. The Fennec project provides a uniquely detailed and comprehensive observational dataset to quantify LLJ processes over the vast expanse of the previously under-observed central Sahara. Here we analyse LLJ characteristics from both the vertical profile data from instruments at the Fennec supersites and the long term data (up to 2 years) from the network of automatic weather stations (AWS). In the case of the AWS data we infer LLJ occurrence from surface winds based on the out-of-phase relationship between the diurnal cycles of (nighttime) LLJ maximum and (mid-morning) surface maximum, driven by the daytime growth of the boundary layer which mixes momentum down from the LLJ to the surface. We find evidence that LLJ are a commonplace feature over the central Sahara occurring on >80% of nights in many stations. The spring (autumn) seasons experience both the highest (lowest) frequency and magnitude. Analysis of the probability density function of wind speeds indicates that LLJs are responsible for the dominant proportion of peak wind speeds greater than typical thresholds suitable for dust emission. We infer that episodic enhancement of LLJ strength through synoptic scale pressure gradients may be the dominant mechanism of dust emission events over the Sahara in all seasons with the exception of summer in the south central Sahara where Haboob features may be more

  4. Comparing environmental changes and habitability settings in the geological history of Sahara and Mars

    Science.gov (United States)

    Ori, G. G.; Sabbadini, R.; Komatsu, G.

    2014-12-01

    Sahara has experienced during its long geological history a large number of climatic changes from humid conditions (with savanna-type environments) to dry conditions (with hot desert environments). Therefore, since the late Miocene (?), Sahara experienced periods with rivers, lakes, deltas, and swamps alternated with dry periods with strong aeolian activity and the formation of deflation surface and sand seas. The fluvio-lacustrine deposits formed during humid periods have been strongly reworked by wind processes during the dry periods leaving only the coarse-grained portion of the sediments (conglomerate to rudite). This highly efficient reworking eeolian mechanism affected both of the fluvial and deltaic channel deposits and the large inland lakes, flood plains and other waterlogged areas. The former occurs, at present day, as morphological features and coarse-grained remnants of large fluvial systems whereas the latter are mostly buried below sand seas such as Grand Erg Oriental, Erg Chech, and Azawad. While the sand to silt material accumulated (mostly by saltation) in the sand seas and sand sheets, the finer portion (able to enter the wind as suspended material) was probably swallowed in the large- scale atmospheric circulation redistributed in Sahara itself, in adjacent continents (mostly Europe and South America), and oceans. This geological setting is similar to the one of Mars where fluvial deposits and morphologies abound as largely eroded discontinuous remains. Large-scale alluvial basins and terminal lakes or waterlogged areas (such as the allucial plain in Zephyria) have been largely present in the Martian Noachian-Hesperian time (and possibly even later) but relatively scanty sedimentary deposits testify their existence. When deposits are present they are basically coarse-grained (e.g. the meandering channels of the Eberswalde deltaic plain) due to the long lasting aeolian erosion similarly than the Sahara example. The wind, that dominated the long

  5. Prevalence of type 2 diabetes in Algerian patients with hepatitis C virus infection

    Science.gov (United States)

    Rouabhia, Samir; Malek, Rachid; Bounecer, Hocine; Dekaken, Aoulia; Amor, Fouzia Bendali; Sadelaoud, Mourad; Benouar, Abderrahmene

    2010-01-01

    AIM: To investigate the prevalence of, and risk factors for, diabetes mellitus (DM) in Algerian patients with chronic hepatitis C virus (HCV) infection and in a control group. METHODS: A cross-sectional study was undertaken. A total of 416 consecutive patients with viral chronic hepatitis attending the Internal Medicine Department of the University Hospital Center Touhami Benflis in Batna [290 HCV-infected and 126 hepatitis B virus (HBV)-infected patients] were prospectively recruited. RESULTS: The prevalence of DM was higher in HCV-infected patients in comparison with HBV-infected patients (39.1% vs 5%, P < 0.0001). Among patients without cirrhosis, diabetes was more prevalent in HCV-infected patients than in HBV-infected patients (33.5% vs 4.3%, P < 0.0001). Among patients with cirrhosis, diabetes was more prevalent in HCV-infected patients, but the difference was not significant (67.4% vs 20%, P = 0.058). The logistic regression analysis showed that HCV infection [odds ratio (OR) 4.73, 95% CI: 1.7-13.2], metabolic syndrome (OR 12.35, 95% CI: 6.18-24.67), family history of diabetes (OR 3.2, 95% CI: 1.67-6.13) and increased hepatic enzymes (OR 2.22, 95% CI: 1.1-4.5) were independently related to DM in these patients. CONCLUSION: The high prevalence of diabetes in HCV-infected patients, and its occurrence at early stages of hepatic disease, suggest that screening for glucose abnormalities should be indicated in these patients. PMID:20632447

  6. Detection and genotyping of Chlamydia species responsible for reproductive disorders in Algerian small ruminants.

    Science.gov (United States)

    Merdja, Salah-Eddine; Khaled, Hamza; Aaziz, Rachid; Vorimore, Fabien; Bertin, Claire; Dahmani, Ali; Bouyoucef, Abdallah; Laroucau, Karine

    2015-02-01

    Chlamydiosis in small ruminants is a zoonotic disease mainly related to Chlamydia abortus. This bacterium is responsible for abortions and reproductive disorders in sheep and goats. Stillbirth and infertility, leading to important economic losses, are also associated with this pathology. In Algeria, abortion cases are frequently reported by veterinarians but, except for brucellosis which is a notifiable disease in this country, abortive diseases are in general poorly studied. In order to detect and genotype Chlamydia species in small ruminants in different areas of Algeria, a study was conducted on samples collected from females (164 blood samples and 199 vaginal swabs) between October 2011 and March 2013. Serum samples were tested with a C. abortus-specific indirect ELISA test. Fourteen samples (8.5 %), from six farms (6/20, 30 %) were tested positive. Vaginal swabs were analysed with a real-time PCR targeting all Chlamydiaceae spp. Thirty samples (15 %) were diagnosed positive in 16 farms (16/25, 64 %). Positive samples were all re-tested with a C. abortus- and a C. pecorum-specific real-time PCR. Finally, 13/30 (43.3 %) and 6/30 (20 %) were identified as C. abortus and C. pecorum, respectively. Enough concentrated C. abortus samples were genotyped by multi-loci variable number of tandem repeat (VNTR) analysis (MLVA), and all were related to the genotype [2] group which mainly includes French C. abortus isolates. C. pecorum-positive samples were genotyped by multi-locus sequence typing (MLST). Interestingly, two of them were successfully genotyped and showed identical MLST sequences to VB2, AB10, E58 and SBE, a group which includes C. pecorum isolates considered as highly pathogenic. These findings suggest a possible role of C. abortus and C. pecorum strains in the aetiology of abortion in Algerian small ruminants.

  7. Context dependence of acorn handling by the Algerian mouse (Mus spretus)

    Science.gov (United States)

    Gallego, D.; Morán-López, T.; Torre, I.; Navarro-Castilla, Á.; Barja, I.; Díaz, M.

    2017-10-01

    Perceived predation risk and competition for acorns are expected to affect scatter-hoarding decisions by Algerian mice (Mus spretus). We manipulated both factors by means of predator fecal scents and ungulate exclosures. We hypothesized that high-risk perception and ungulate presence would promote acorn dispersal. In the former case, it would stimulate acorn mobilization to safe microhabitats rather than in situ consumption. In the latter, increased competition for acorns would promote their storage for later consumption. We also expected that mice would adapt their foraging behavior to previous experience modulating the strength of these effects. In the presence of ungulates, mice focused their foraging activities on food acquisition at the expenses of vigilant behaviors. However, a more efficient foraging did not entail enhanced dispersal services. Lack of anti-predatory cover in tree surroundings may have deterred mice from transporting seeds outside canopies. Increased risk interacted with previous experience. In control trees (no predator odor), mice confidence increased throughout the night resulting in decreased vigilance and enhanced acorn mobilization rates. In contrast, in risky conditions (trees with predator odor) mice maintained a base-line vigilant behavior. Contrary to our expectations, increased risk did not result in higher acorn mobilization, but the opposite. Again, the scarcity of safe microhabitats for mobilization may have been the underlying cause of this behavior. Our results show that successful acorn dispersal depends, at least partly, on plant-animal relationships that are beyond the oak-rodent mutualism. Thus, any conservation policy aimed at restoring natural regeneration of oaks should take into account the interaction network in which oak-rodent encounters are embedded. In addition, they suggest that mice incorporate direct and indirect cues of risks (habitat structure) through recent experience. A better understanding of this process

  8. Safety culture assessment in petrochemical industry: a comparative study of two algerian plants.

    Science.gov (United States)

    Boughaba, Assia; Hassane, Chabane; Roukia, Ouddai

    2014-06-01

    To elucidate the relationship between safety culture maturity and safety performance of a particular company. To identify the factors that contribute to a safety culture, a survey questionnaire was created based mainly on the studies of Fernández-Muñiz et al. The survey was randomly distributed to 1000 employees of two oil companies and realized a rate of valid answer of 51%. Minitab 16 software was used and diverse tests, including the descriptive statistical analysis, factor analysis, reliability analysis, mean analysis, and correlation, were used for the analysis of data. Ten factors were extracted using the analysis of factor to represent safety culture and safety performance. The results of this study showed that the managers' commitment, training, incentives, communication, and employee involvement are the priority domains on which it is necessary to stress the effort of improvement, where they had all the descriptive average values lower than 3.0 at the level of Company B. Furthermore, the results also showed that the safety culture influences the safety performance of the company. Therefore, Company A with a good safety culture (the descriptive average values more than 4.0), is more successful than Company B in terms of accident rates. The comparison between the two petrochemical plants of the group Sonatrach confirms these results in which Company A, the managers of which are English and Norwegian, distinguishes itself by the maturity of their safety culture has significantly higher evaluations than the company B, who is constituted of Algerian staff, in terms of safety management practices and safety performance.

  9. Assessment of radiation protection of patients and staff in interventional procedures in four Algerian hospitals

    International Nuclear Information System (INIS)

    Khelassi-Toutaoui, N.; Toutaoui, A.; Merad, A.; Sakhri-Brahimi, Z.; Baggoura, B.; Mansouri, B.

    2016-01-01

    This study was aimed to assess patient dosimetry in interventional cardiology (IC) and radiology (IR) and radiation safety of the medical operating staff. For this purpose, four major Algerian hospitals were investigated. The data collected cover radiation protection tools assigned to the operating staff and measured radiation doses to some selected patient populations. The analysis revealed that lead aprons are systematically worn by the staff but not lead eye glasses, and only a single personal monitoring badge is assigned to the operating staff. Measured doses to patients exhibited large variations in the maximum skin dose (MSD) and in the dose area product (DAP). The mean MSD registered values are as follows: 0.20, 0.14 and 1.28 Gy in endoscopic retrograde cholangio-pancreatography (ERCP), coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA) procedures, respectively. In PTCA, doses to 3 out of 22 patients (13.6 %) had even reached the threshold value of 2 Gy. The mean DAP recorded values are as follows: 21.6, 60.1 and 126 Gy cm 2 in ERCP, CA and PTCA procedures, respectively. Mean fluoroscopic times are 2.5, 5 and 15 min in ERCP, CA and PTCA procedures, respectively. The correlation between DAP and MSD is fair in CA (r = 0.62) and poor in PTCA (r = 0.28). Fluoroscopic time was moderately correlated with DAP in CA (r = 0.55) and PTCA (r = 0.61) procedures. Local diagnostic reference levels (DRLs) in CA and PTCA procedures have been proposed. In conclusion, this study stresses the need for a continuous patient dose monitoring in interventional procedures with a special emphasis in IC procedures. Common strategies must be undertaken to substantially reduce radiation doses to both patients and medical staff. (authors)

  10. Extraction of essential oils from Algerian myrtle leaves using instant controlled pressure drop technology.

    Science.gov (United States)

    Berka-Zougali, Baya; Hassani, Aicha; Besombes, Colette; Allaf, Karim

    2010-10-01

    In the present work, the new extraction process of Détente Instantanée Contrôlée DIC (French, for instant controlled pressure drop) was studied, developed, quantitatively and qualitatively compared to the conventional hydrodistillation method for the extraction of essential oils from Algerian myrtle leaves. DIC was used as a thermomechanical treatment, DIC subjecting the product to a high-pressure saturated steam. The DIC cycle ends with an abrupt pressure drop towards vacuum, and this instantly leads to an autovaporization of myrtle volatile compounds. An immediate condensation in the vacuum tank produced a micro-emulsion of water and essential oils. Thus, an ultra-rapid cooling of residual leaves occurred, precluding any thermal degradation. An experimental protocol was designed with 3 independent variables: saturated steam pressure between 0.1 and 0.6 MPa, resulting in a temperature between 100 and 160°C, a total thermal processing time between 19 and 221 s, and between 2 and 6 DIC cycles. The essential oils yield was defined as the main dependent variable. This direct extraction gave high yields and high quality essential oil, as revealed by composition and antioxidant activity (results not shown). After this treatment, the myrtle leaves were recovered and hydrodistilled in order to quantify the essential oil content in residual DIC-treated samples. Scanning electron microscope (SEM) showed some modification of the structure with a slight destruction of cell walls after DIC treatment. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Prevalence of type 2 diabetes in Algerian patients with hepatitis C virus infection.

    Science.gov (United States)

    Rouabhia, Samir; Malek, Rachid; Bounecer, Hocine; Dekaken, Aoulia; Bendali Amor, Fouzia; Sadelaoud, Mourad; Benouar, Abderrahmene

    2010-07-21

    To investigate the prevalence of, and risk factors for, diabetes mellitus (DM) in Algerian patients with chronic hepatitis C virus (HCV) infection and in a control group. A cross-sectional study was undertaken. A total of 416 consecutive patients with viral chronic hepatitis attending the Internal Medicine Department of the University Hospital Center Touhami Benflis in Batna [290 HCV-infected and 126 hepatitis B virus (HBV)-infected patients] were prospectively recruited. The prevalence of DM was higher in HCV-infected patients in comparison with HBV-infected patients (39.1% vs 5%, P < 0.0001). Among patients without cirrhosis, diabetes was more prevalent in HCV-infected patients than in HBV-infected patients (33.5% vs 4.3%, P < 0.0001). Among patients with cirrhosis, diabetes was more prevalent in HCV-infected patients, but the difference was not significant (67.4% vs 20%, P = 0.058). The logistic regression analysis showed that HCV infection [odds ratio (OR) 4.73, 95% CI: 1.7-13.2], metabolic syndrome (OR 12.35, 95% CI: 6.18-24.67), family history of diabetes (OR 3.2, 95% CI: 1.67-6.13) and increased hepatic enzymes (OR 2.22, 95% CI: 1.1-4.5) were independently related to DM in these patients. The high prevalence of diabetes in HCV-infected patients, and its occurrence at early stages of hepatic disease, suggest that screening for glucose abnormalities should be indicated in these patients.

  12. Safety Culture Assessment in Petrochemical Industry: A Comparative Study of Two Algerian Plants

    Science.gov (United States)

    Boughaba, Assia; Hassane, Chabane; Roukia, Ouddai

    2014-01-01

    Background To elucidate the relationship between safety culture maturity and safety performance of a particular company. Methods To identify the factors that contribute to a safety culture, a survey questionnaire was created based mainly on the studies of Fernández-Muñiz et al. The survey was randomly distributed to 1000 employees of two oil companies and realized a rate of valid answer of 51%. Minitab 16 software was used and diverse tests, including the descriptive statistical analysis, factor analysis, reliability analysis, mean analysis, and correlation, were used for the analysis of data. Ten factors were extracted using the analysis of factor to represent safety culture and safety performance. Results The results of this study showed that the managers' commitment, training, incentives, communication, and employee involvement are the priority domains on which it is necessary to stress the effort of improvement, where they had all the descriptive average values lower than 3.0 at the level of Company B. Furthermore, the results also showed that the safety culture influences the safety performance of the company. Therefore, Company A with a good safety culture (the descriptive average values more than 4.0), is more successful than Company B in terms of accident rates. Conclusion The comparison between the two petrochemical plants of the group Sonatrach confirms these results in which Company A, the managers of which are English and Norwegian, distinguishes itself by the maturity of their safety culture has significantly higher evaluations than the company B, who is constituted of Algerian staff, in terms of safety management practices and safety performance. PMID:25180135

  13. Quantifying the role of sandy-silty sediments in generating slope failures during earthquakes: example from the Algerian margin

    Science.gov (United States)

    Dan, Gabriela; Sultan, Nabil; Savoye, Bruno; Deverchere, Jacques; Yelles, Karim

    2009-06-01

    The Algerian margin is a seismically active region, where during the last century, several large magnitude earthquakes took place. This study combines geotechnical and sedimentological data with numerical modelling to quantitatively assess the present-day slope stability of the Algerian margin. Geotechnical laboratory tests, such as cyclic triaxial tests, oedometric tests and vane shear tests were carried out on sediment cores collected on the study area. The liquefaction potential of a sediment column located about 30 km from the Boumerdès earthquake epicentre of 21st May 2003 was evaluated theoretically for an earthquake of M w = 6.8. We show that thin sand and silt beds such as those described on recovered sediment cores are the main cause of sediment deformation and liquefaction during earthquakes. Numerical calculations showed that the slope failure may occur during an earthquake characterised by a PGA in excess of 0.1 g, and also that, under a PGA of 0.2 g liquefaction could be triggered in shallow silty-sandy deposits. Moreover, comparison of the predicted slope failure with failure geometries inferred from seafloor morphology showed that earthquakes and subsequent mass movements could explain the present-day morphology of the study area.

  14. [Metabolic syndrome and hormonal interaction in obese and type 2 diabetic Algerian subject: the behavior eating disorder impact].

    Science.gov (United States)

    Koceïr, E A; Benbaïbeche, H; Haffaf, El M; Kacimi, G; Oudjit, B

    2009-01-01

    These twenty last years, the metabolic syndrome was accused in various human pathologies including android obesity and type 2 diabetes. In obesity, increased body weight is frequently associated with excessive caloric food and sedentary activities. The Behaviour Eating Disorders (BED) is involved in over-consumption alimentary. In Algeria, we observed increasingly deviations in life-style alimentary, from the Mediterranean-Cretan model to American fast-food model. To study interactions between the BED, hormonal secretions and metabolic syndrome parameters. The present study was undertaken on Algerian population cohorts composed of 30 obese subjects, 70 type 2 diabetic patients and 30 healthy subjects. The BED was evaluated by TFEQ and DEBQ tests. Anthropometric parameters (waist circumference, IMC), metabolic parameters (glucose, triglycerides, HDL-C, LDL-C) and hormones (insulin, peptide C, ACTH, cortisol, GH) were determinates by biometrics, spectrophotometry and radioimmunology methods, respectively. Multivariate analyses showed the high correlation between the BED and the metabolic syndrome, particularly a critical insulinoresistance state (IR). This IR generates in periphery a whole of metabolic disorders: dyslipidemia, hyperglycemia and hypertrophy of adipose tissue. In diabetic and obese patients, cortisol, ACTH and GH secretions are insidiously altered and to lead metabolic disorders. In this study, the role of the BED in obesity and diabetes genesis seems to be confirmed. In response to nutritional stress, the BED generates a hyperactivity of endocrine pancreas, adrenal gland, and pituitary gland. It appeared that Algerian population is not adapted to fast-food American model.

  15. Le rôle des facteurs locaux sur les effets des changements climatiques au Quaternaire supérieur sur les environnements naturel du Néguev septentrional

    Directory of Open Access Journals (Sweden)

    Aaron Yair

    2010-10-01

    Full Text Available Les régions sèches sont souvent considérées sensibles aux changements climatiques. Pour ces régions, une relation positive est souvent proposée entre la pluie annuelle moyenne et les données de l'environnement, par des scientifiques appartenant à des disciplines diverses. Cependant les modèles climatiques globaux sont encore incapables de prévoir d'une façon précise l'évolution du climat à l'échelle régionale et ses effets possibles sur l'environnement. De plus, ces modèles sont impuissants à traduire l'influence que des facteurs non climatiques tels que la lithologie et les sols, ainsi que des facteurs biologiques, exercent sur la répartition de l'eau dans l'espace et le temps. En d'autres termes, le même changement climatique régional prévu aura probablement des effets différents dans les secteurs rocheux, lœssiques ou sableux. Le Néguev septentrional offre des conditions très favorables pour l'étude des effets possibles du changement climatique prévu, le long d'un gradient pluviométrique régional où les unités physiographiques varient dans l'espace. Deux cas sont considérés. Le premier traite des effets sur l'environnement du dépôt d'un couvert lœssique lors d'une phase climatique humide au Quaternaire supérieur. Le second examine l'influence de croûtes biologiques de surface sur le régime hydrique d'une zone sableuse le long d'un gradient pluviométrique actuel. Dans les deux cas, le gradient pluviométrique est accompagné par d'autres gradients (géomorphologiques, pédologiques, biologiques. Les données obtenues attirent l'attention sur les relations complexes entre le gradient pluviométrique et les autres gradients, qui peuvent entraîner des effets négatifs sur les ressources hydriques et sur la qualité de l'environnement.Dryland areas are usually regarded as highly sensitive to climate change. A positive relationship between average annual rainfall and environmental variables is often assumed

  16. Two Oil Types on the North Slope of Alaska. Implications for Future Exploration Les deux types d'huile du versant septentrional de l'Alaska. Implications pour l'exploration future

    Directory of Open Access Journals (Sweden)

    Magoon L. B.

    2006-10-01

    Full Text Available Forty oil samples from across the North Slope of Alaska have been analyzed by the US Bureau of Mines and the Us Geological Survey. Results of these analyses suggest two separate genetic oil types. The first type, the Simpson-Umiat oil type, occurs in reservoir rocks of Cretaceous and Quaternary age and includes oils from seeps in the Skull Cliff, Cape Simpson, Manning Point, and Ungoon Point areas; the Wolf Creek test well 3, and the Umiat oil field. These are higher gravity, low-sulfur oils with no, or slight, odd-numbered n-alkane predominance and pristane to phytane ratios greater than 1. 5. The second type, the Barrow-Prudhoe oil type, occurs in reservoir rocks of Carboniferous to Cretataceous age and includes ails from South Barrow gas field, Prudhoe Bay oil field, and the Fish Creek test well 1. Physical properties of Barrow-Prudhoe oils are variable, but in general the oils are medium-gravity, high-sulfur oils with a slight even-numbered n-alkane predominance and pristane to phytane ratio of less thon 1. 5. The two types are believed to originated from different source rocks; the Barrow-Prudhoe type may have originated from a carbonate or other iron-deficient source rock, and the Simpson-Umiat type from asiliciclastic source rock. Occurrences of fine two oil types, when outlined on a map, indicate atleast two exploration fairways. The fairway for the Barrow-Prudhoe type is along the Barrow arch, and the fairway, for the Simpson-Umiat type is the area of the best reservoir development for the Nanushuk Group. Quarante échantillons d'huile prélevés à travers le versant septentrional de l'Alaska ont été analysés par l'US Bureau of Mines et l'US Geological Survey. Les résultats de ces analyses suggèrent deux types séparés d'huile. Le premier, le type d'huile Simpson-Umiat, se trouve dans des roches magasins du Crétacé au Quaternaire et comprend des huiles des suintements des régions de la falaise Skull, du cap Simpson, de Point

  17. Impacts of climate variability and change on crop yield in sub-Sahara Africa

    Science.gov (United States)

    Pan, S.; Zhang, J.; Yang, J.; Chen, G.; Xu, R.; Zhang, B.; Lou, Y.

    2017-12-01

    Much concern has been raised about the impacts of climate change and climate extremes on Africa's food security. The impact of climate change on Africa's agriculture is likely to be severe compared to other continents due to high rain-fed agricultural dependence, and limited ability to mitigate and adapt to climate change. In recent decades, warming in Africa is more pronounced and faster than the global average and this trend is likely to continue in the future. However, quantitative assessment on impacts of climate extremes and climate change on crop yield has not been well investigated yet. By using an improved agricultural module of the Dynamic Land Ecosystem Model (DLEM-AG2) driven by spatially-explicit information on land use, climate and other environmental changes, we have assessed impacts of historical climate variability and future climate change on food crop yield across the sub-Sahara Africa during1980-2016 and the rest of the 21st century (2017-2099). Our simulated results indicate that African crop yield in the past three decades shows an increasing trend primarily due to cropland expansion. However, crop yield shows substantially spatial and temporal variation due to inter-annual and inter-decadal climate variability and spatial heterogeneity of environmental drivers. Droughts have largely reduced crop yield in the most vulnerable regions of Sub-Sahara Africa. Future projections with DLEM-AG2 show that food crop production in Sub-Sahara Africa would be favored with limiting end-of-century warming to below 1.50 C.

  18. [Hypotheses on the role of the prehistoric Sahara in the spread of parasitic and hematologic diseases].

    Science.gov (United States)

    Nozais, J P

    1987-01-01

    15,000 years ago, the Sahara was moist, inhabited by tropical fauna and travelled over by nomadic populations. Later, the dryness incited human migrations to North or West Africa. African bilharziasis (S. mansoni and S. haematobium) could have been carried by nomadic populations infected in the Nile River. Sickle cell disease and alpha-thalassemia are derived from Saudi Arabia (unless in the case of alpha-thalassemia there was an identical mutation in several regions). Echinococcosis was brought with the dromedary in the ptolemaic era whereas ankylostomiasis was brought by the Romans or the Arabs.

  19. TL and ESR of quartz from the astrobleme of Aorounga (Sahara of Chad)

    OpenAIRE

    Miallier, Didier; Sanzelle, S.; Falgueres, C.; Fain, Jean; Pilleyre, Thierry; Vincent, P.M.

    1997-01-01

    International audience; The present work was intended to evaluate the time that elapsed since the meteorite fall that produced-the giant astrobleme of Aorounga (Sahara ot'Chad". For this purpose the TL and ESR dating techniques using the additive dose method were applied to quartz grains extracted f'rom an impactite and from a sandstone shocked and haked during the impact. The ESR Al centre was measured and resulted in an âge or about 800 ka. The red TL and the blue TL showed unusual TL featu...

  20. Short-Circuit Calculations for a Transmission Line in the Algerian Power Network Compensated by Thyristor Controlled Voltage Regulator

    Directory of Open Access Journals (Sweden)

    ZELLAGUI Mohamed

    2014-10-01

    Full Text Available In this paper, the impact of using the Thyristor Controlled Voltage Regulator (TCVR on short-circuit calculations is studied for a high voltage transmission line in case of a phase to earth fault in the presence of a fault resistance (RF. A 400 kV single transmission line, in the Algerian power network, is used for this study where the line is compensated by TCVR FACTS device to control the voltage and active power of the line. The impact of the fault resistance is studied to reflect its effect on short-circuit calculations including symmetrical current components, transmission line currents, voltage symmetrical components, and transmission line voltages, without and with TCVR. The obtained simulation results match the presented theoretical analysis.

  1. Bacillus amyloliquefaciens ssp. plantarum F11 isolated from Algerian salty lake as a source of biosurfactants and bioactive lipopeptides.

    Science.gov (United States)

    Daas, Mohamed Seghir; Acedo, Jeella Z; Rosana, Albert Remus R; Orata, Fabini D; Reiz, Béla; Zheng, Jing; Nateche, Farida; Case, Rebecca J; Kebbouche-Gana, Salima; Vederas, John C

    2018-01-01

    In this study, we identified a new Bacillus strain isolated from an Algerian salty lake that produces metabolites that are active against Gram-positive and Gram-negative bacteria, as well as fungal pathogens. The draft genome sequence of the strain is presented herein. Genome sequence analysis identified the strain to be B. amyloliquefaciens subspecies plantarum F11, and showed that the strain carries the gene clusters for the production of a number of bioactive and surface-active compounds. These include the lipopeptides surfactin and fengycin, antibacterial polyketides macrolactin and bacillaene, and a putative novel lanthipeptide, among others. Through an activity-guided purification method using hydrophobic interaction chromatographic techniques, we confirmed the ability of the strain to produce fengycin lipopeptides. The identities of the isolated fengycin homologs were ascertained through tandem mass spectrometry. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. The Algerian gas is on the verge of changing its religion; Le gaz algerien en passe de changer de religion

    Energy Technology Data Exchange (ETDEWEB)

    El Kadi, I.

    2009-07-01

    Algeria has not forged, during the years 2000, a natural gas 'diplomacy' comparable - by far - to the Russian one. Three obstacles were on its way: first, proved reserves are six time less than those of the top world producer; secondly, its maneuver margin has been for a long time reduced by long term supply contracts (to South Europe essentially); thirdly, Algeria experienced a great political difficulty to define a strategy that could be adapted to the new world context of rarefied energy sources, a context that is clearer since 2003-2004. The author explains the changes that have happened within these three constraint lines since 2008. He notably comments the geopolitical incidence of the end of the long term sale contracts, the role of LNG in the global energy mix, and analyses the Algerian gas production perspectives and the possibility of an agreement between gas producing countries

  3. Optical and spectroscopic characterizations of Algerian silica raw material to predict high quality solar-grade silicon

    Science.gov (United States)

    Kheloufi, A.; Bobocioiu, E.; Kerkar, F.; Kefaifi, A.; Anas, S.; Medjahed, S. A.; Belkacem, Y.; Keffous, A.

    2017-03-01

    We assess the potential use as raw material for photovoltaics of Algerian silica samples from the quartz veins of the Tirek deposit and quartz sandstones of the Ain Barda deposit. With 97-98% purity, they all require enrichment before their industrial utilization. Acid leaching and gravimetric separation are used to remove the impurities at the grain boundaries and within the crystal lattice. We obtain course, middle, and fine products. The acid leaching process and the gravimetric separation increase the content of SiO2 up to 99.68%; the residue concentration of iron, alumina and zirconium is decreased to 70, 72 and 58 ppm respectively. These values are in agreement with requirements for silica as raw material destined for solar-grade silicon production.

  4. Eolian sediment responses to late Quaternary climate changes: Temporal and spatial patterns in the Sahara

    Science.gov (United States)

    Swezey, C.

    2001-01-01

    This paper presents a compilation of eolian-based records of late Quaternary climate changes in the Sahara. Although the data are relatively sparse, when viewed as a whole, they reveal a general pattern of widespread eolian sediment mobilization prior to 11,000 cal. years BP, eolian sediment stabilization from 11,000 to 5000 cal. years BP, and a return to widespread eolian sediment mobilization after 5000 cal. years BP. Furthermore, an eolian-based record from southern Tunisia reveals the existence of millennial-scale changes in eolian sediment behavior. These millennial-scale variations provide examples of eolian sediment responses to climate changes at a scale intermediate between seasonal and orbital ('Milankovitch') changes, and they are also coincident with abrupt atmospheric and oceanic changes. The general synchroneity of the eolian stratigraphic records and their coincidence with various oceanic and atmospheric changes suggest that global forcing mechanisms have influenced late Quaternary eolian sediment behavior in the Sahara. ?? 2001 Elsevier Science B.V.

  5. Impact of Sahara dust transport on Cape Verde atmospheric element particles.

    Science.gov (United States)

    Almeida-Silva, M; Almeida, S M; Freitas, M C; Pio, C A; Nunes, T; Cardoso, J

    2013-01-01

    The objectives of this study were to (1) conduct an elemental characterization of airborne particles sampled in Cape Verde and (2) assess the influence of Sahara desert on local suspended particles. Particulate matter (PM(10)) was collected in Praia city (14°94'N; 23°49'W) with a low-volume sampler in order to characterize its chemical composition by k0-INAA. The filter samples were first weighed and subsequently irradiated at the Portuguese Research Reactor. Results showed that PM(10) concentrations in Cape Verde markedly exceeded the health-based air quality standards defined by the European Union (EU), World Health Organization (WHO), and U.S. Environmental Protection Agency (EPA), in part due to the influence of Sahara dust transport. The PM(10) composition was characterized essentially by high concentrations of elements originating from the soil (K, Sm, Co, Fe, Sc, Rb, Cr, Ce, and Ba) and sea (Na), and low concentrations of anthropogenic elements (As, Zn, and Sb). In addition, the high concentrations of PM measured in Cape Verde suggest that health of the population may be less affected compared with other sites where PM(10) concentrations are lower but more enriched with toxic elements.

  6. Meningkatkan Profesionalisme Guru Melalui Implementasi Manajemen Berbasis Sekolah (MBS Di SD Sahara Kabupaten Bandung

    Directory of Open Access Journals (Sweden)

    Bambang Suprihatin

    2017-10-01

    Full Text Available This study aims to determine the teachers’ professionalism through the implementation of School Based Management (SBM in SAHARA elementary school. The study applies qualitative approach with descriptive. The subject of this research is SAHARA elementary school, consists of ten people selected by purposive sampling technique. The study collected the data by using observation and interview. The data is processed by reducing the data, presenting the data, and drawing conclusion. The result indicates that the principal discusses the policy which will be applied by school. Moreover, the principal evaluates the progress by checking the learning device, teachers’ attendance, students’ learning achievement and the Teacher Competency Test conducted in cluster. The undertaken efforts clearly show the impact on the graduation of the first year. All the students are graduated with satisfactory result. It proves that the school achievement gained through the students’ success, the teachers maximizes the time on the teaching and learning process, teachers use various learning media. There is students have an increase in learning outcomes. Therefore, the improvement in teacher professionalism is through the implementation of school-based management.

  7. DETERMINANTS OF AGRICULTURAL PRODUCTIVITY GROWTH IN SUB-SAHARA AFRICA: 1961-2003

    Directory of Open Access Journals (Sweden)

    Olajide Abraham Ajao

    2012-12-01

    Full Text Available This study examined changes in agricultural productivity in Sub-Sahara Africa countries in the context of diverse institutional arrangements using Data Envelopment Analysis (DEA. From a time series which consists of information on agricultural production and means of production were obtained from FAO AGROSTAT and rainfall data from Steve O’Connell data base. The information was for a 43-year period (1961-2003; DEA method was used to measure Malmquist index of total factor productivity. A decomposition of TFP measures revealed that the observed increase in the TFP in the sub–Sahara Africa agriculture is due to technological change rather than efficiency change which is the main constrained of achieving higher level of TFP during the reference period. The study further examined the effect of land quality, malaria, education and selected governance indicators such as, control of corruption and government effectiveness on productivity growth. All the variables included in the model are significant with the exception of government effectiveness

  8. Ovulation rate and early embryonic survival rate in female rabbits of a synthetic line and a local Algerian population

    Directory of Open Access Journals (Sweden)

    R. Belabbas

    2016-12-01

    Full Text Available A higher litter size at birth has been reported in female rabbits from a Synthetic line than in those of the Local Algerian population. The aim of this work was to analyse whether this difference in litter size was due to a higher ovulation rate and/or embryonic survival rate in Synthetic line than in Local Algerian population. In total, 24 multiparous female rabbits from Synthetic line and 23 from Local population were used in this experiment. Litter size at birth was recorded up to the first 3 parities. Litter size was 20% higher in Synthetic line than Local population. At their 4th gestation, the females were euthanized at 72 h post coitum. Synthetic line females had 50% more ova and embryos than those of Local population (+4.42 ova and +3.92 embryos, respectively. Synthetic line displayed a lower percentage of normal embryos and a larger number of unfertilized oocytes than Local population (–2.81% and +0.64 oocytes, respectively, but differences were not relevant. Synthetic line showed a lesser embryonic stage of development at 72 h post coitum, showing a higher percentage of early morulae (31.50 vs. 8.50% and a lower percentage of compact morulae (51.45 vs. 78.65% than Local population. No relevant difference was found for early embryonic survival rate between Synthetic line and Local population. In conclusion, the difference in litter size was mainly due to a higher ovulation rate in the Synthetic line, allowing more embryos to develop in this line.

  9. Association analysis of the IL-1 gene cluster polymorphisms with aggressive and chronic periodontitis in the Algerian population.

    Science.gov (United States)

    Boukortt, Kawther Nourelhouda; Saidi-Ouahrani, Nadjia; Boukerzaza, Boubaker; Ouhaibi-Djellouli, Hadjira; Hachmaoui, Khalida; Benaissa, Fatima Zohra; Taleb, Leila; Drabla-Ouahrani, Hayet; Deba, Tahria; Ouledhamou, Sid Ahmed; Mehtar, Nadhera; Boudjema, Abdellah

    2015-10-01

    There is strong evidence that genetic as well as environmental factors affect the development of periodontitis. Various studies suggest that genetic polymorphisms of the interleukin-1 (IL-1) genes are associated with an increased risk of developing the pathogenesis. The aim of the present study was to investigate the possible relationship between two polymorphisms of IL-1 gene cluster IL-1B (C+3954T) (rs1143634) and IL-1A (C-889T) (rs1800587) SNPs and the aggressive and chronic periodontitis risk in a case control study in Algerian population. 279 subjects were recruited and received a periodontal examination: 128 healthy controls and 151 cases. From cases, 91 patients were having a chronic disease whereas 60 subjects with aggressive form. All these subjects were genotyped for IL-1A (C-889T) and IL-1B (C+3954T) polymorphisms using TaqMan real time PCR technology. Frequencies of IL-1 alleles, genotypes and the haplotypes were also examined. Significant differences were found in the carriage rate of both minor alleles of the IL-1A (C-889T) and IL-1B (C+3954T) polymorphisms of aggressive periodontitis cases compared with healthy controls (OR [95%CI]=1.61 [1.03-2.49], p=0.03), (OR [95%CI]=1.69 [1.09-2.63], p=0.01), respectively. The result did not reach significance with the chronic form. The studied polymorphisms of the IL-1 genes appear to be associated with susceptibility to aggressive periodontitis (AgP) in the Algerian population. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Preliminary comparative study of anti-inflmmatory effect of unheated and heat-treated Sahara honey: In vivo approach

    Directory of Open Access Journals (Sweden)

    Moussa Ahmed

    2015-11-01

    Full Text Available Objective: To investigate the effect of unheated and heat-treated of Sahara honey. Methods: A total of 24 Swiss albino mice weighing 25–35 g were divided into four groups (n = 6. Anti-inflammatory effect was assessed at 1, 2, 3, 4, 5 and 6 h after subplantar injection of carrageenan (0.5 mL of a 1% solution in normal saline. In addition, total phenolic content was determined by modified Folin-Ciocalteu method. Results: The total phenolic content capacity of the Sahara honey before and after heat treatment was between 72 and 97.9 mg of gallic acid equivalents/100 g of honey respectively. Administration of unheated honey (oral administration reduced significantly (P < 0.05. The carrageenan induced mice paw edema model at 1, 3 and 6 h for 21.85%, 5.43% and 80.43%, respectively. Administration of heat-treated honey showed insignificant inhibition of carrageenan and induced paw edema at 1 h (31.16%, 3 h (0.25% and 6 h (34.19%. The 50 mg/kg diclofenac exhibited percent reduction in paw volume 16.12%, 8.90% and 15.32% after 1 h, 3 h and 6 h, respectively, when compared with control animals. No toxicity was identified. Conclusions: Our results suggest that unheated Sahara honey has anti-inflammatory effects by reducing the mice paw edema size while heat-treated Sahara honey decreases the antiinflammatory activity.

  11. Declines in a ground-dwelling arthropod community during an invasion by Sahara mustard (Brassica tournefortii) in aeolian sand habitats

    Science.gov (United States)

    Heather L. Hulton VanTassel; Anne M. Hansen; Cameron W. Barrows; Quresh Latif; Margaret W. Simon; Kurt E. Anderson

    2014-01-01

    Sahara Mustard (Brassica tournefortii; hereafter mustard), an exotic plant species, has invaded habitats throughout the arid southwestern United States. Mustard has reached high densities across aeolian sand habitats of southwestern deserts, including five distinct sand habitats in the eastern Coachella Valley, California. We examined trends in ground-dwelling...

  12. Long-distance autumn migration across the Sahara by painted lady butterflies: exploiting resource pulses in the tropical savannah.

    Science.gov (United States)

    Stefanescu, Constantí; Soto, David X; Talavera, Gerard; Vila, Roger; Hobson, Keith A

    2016-10-01

    The painted lady, Vanessa cardui, is a migratory butterfly that performs an annual multi-generational migration between Europe and North Africa. Its seasonal appearance south of the Sahara in autumn is well known and has led to the suggestion that it results from extremely long migratory flights by European butterflies to seasonally exploit the Sahel and the tropical savannah. However, this possibility has remained unproven. Here, we analyse the isotopic composition of butterflies from seven European and seven African countries to provide new support for this hypothesis. Each individual was assigned a geographical natal origin, based on its wing stable hydrogen isotope (δ 2 H w ) value and a predicted δ 2 H w basemap for Europe and northern Africa. Natal assignments of autumn migrants collected south of the Sahara confirmed long-distance movements (of 4000 km or more) starting in Europe. Samples from Maghreb revealed a mixed origin of migrants, with most individuals with a European origin, but others having originated in the Sahel. Therefore, autumn movements are not only directed to northwestern Africa, but also include southward and northward flights across the Sahara. Through this remarkable behaviour, the productive but highly seasonal region south of the Sahara is incorporated into the migratory circuit of V. cardui. © 2016 The Author(s).

  13. Diversity of Microbial Communities in Production and Injection Waters of Algerian Oilfields Revealed by 16S rRNA Gene Amplicon 454 Pyrosequencing

    OpenAIRE

    Lenchi, Nesrine; ?nceo?lu, ?zg?l; Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Llir?s, Marc; Servais, Pierre; Garc?a-Armisen, Tamara

    2013-01-01

    The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three...

  14. Chemical and biological evaluation of the nutritive value of Algerian green seaweed Ulva lactuca using in vitro gas production technique fior ruminant animals

    OpenAIRE

    Zitouni, Hind; Arhab, Rabah; Boudry, Christelle; Bousseboua, Hacène; Beckers, Yves

    2014-01-01

    This study aimed to determine the nutritive value of seaweed Ulva lactuca collected from the Algerian coast by estimation of its chemical composition and fermentation characteristics, comparatively to vetch-oat hay (control), using in vitro gas production technique. Seaweed and control were incubated with rumen liquor taken from fistulated and non lactating cows. Gas production was recorded at: 2, 4, 6, 8, 12, 24, 48 and 72h. The in vitro rumen fermentation parameters were measured after 24h ...

  15. Shock Metamorphism of L6 Chondrites Sahara 98222 and Yamato 74445: the P-T Conditions and the Shock age

    Science.gov (United States)

    Ozawa, S.; Ohtani, E.; Suzuki, A.; Miyahara, M.; Terada, K.; Kimura, M.

    2007-12-01

    Impact phenomena are the fundamental processes of accretion of the terrestrial planets. Therefore, investigations of meteorites that experienced shock events are useful for understanding mechanisms of planetary impact events and formation of terrestrial planets. Heavily shocked meteorites contain abundant shock melt veins, where some high-pressure minerals have been discovered. In this study, we investigated mineralogy of shock melt veins of two L6 chondrites (Sahara 98222 and Yamato 74445) and estimated the P-T conditions during their impact events.We found that the shock melt veins of these meteorites contain several high-pressure minerals such as wadsleyite, jadeite and tuite for Sahara 98222 and ringwoodite (+ wadsleyite), akimotoite and lingunite for Yamato 74445. Tuite is a high-pressure polymorph of whitlockite and lingunite is a high-pressure polymorph of albite with hollandite structure. Based on mineralogy in the shock veins; we estimated the pressure and temperature conditions during their impact events: 13-15 GPa, > 2000°C for Sahara 98222 and 15- 24 GPa, > 2200°C for Yamato 74445, respectively.We also conducted a U-Pb dating of phosphates in and around the shock melt veins of Sahara 98222 using a Sensitive High Resolution Ion Micro Probe (SHRIMP-II) at Hiroshima University to reveal when this shock event occurred. We obtained following radioactive ages: Pb-Pb isochron age: 4466 ± 31 Ma; U-Pb isochron age: 4498 ± 150 Ma; Total U-Pb isochron age: 4467 ± 22 Ma. These ages seem to be slightly younger than the previously reported ages of chondrites, which are usually older than 4500 Ma. This could suggest that Sahara 98222 have recorded a shock event in the very early stage of the solar system where the planetary formation was going on.

  16. Tissues and hair residues and histopathology in wild rats (Rattus rattus L.) and Algerian mice (Mus spretus Lataste) from an abandoned mine area (Southeast Portugal)

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, R. [Departamento de Biologia da Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal) and Instituto Piaget, Campus Academico de Viseu, Estrada do Alto do Gaio, Lordosa, 3515-776 Viseu (Portugal)]. E-mail: ruthp@bio.ua.pt; Pereira, M.L. [Departamento de Biologia da Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Ribeiro, R. [Instituto do Ambiente e Vida, Departamento de Zoologia da Universidade de Coimbra, Largo Marques de Pombal, 3004-517 Coimbra (Portugal); Goncalves, F. [Departamento de Biologia da Universidade de Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

    2006-02-15

    Data gathered in this study suggested the exposure of rats and Algerian mice, living in an abandoned mining area, to a mixture of heavy metals. Although similar histopathological features were recorded in the liver and spleen of both species, the Algerian mouse has proved to be the strongest bioaccumulator species. Hair was considered to be a good biological material to monitor environmental contamination of Cr in rats. Significant positive associations were found between the levels of this element in hair/kidney (r = 0.826, n = 9, p < 0.01) and hair/liver (r = 0.697, n = 9, p = 0.037). Although no association was found between the levels of As recorded in the hair and in the organs, the levels of this element recorded in the hair, of both species, were significantly higher in animals captured in the mining area, which met the data from the organs analysed. Nevertheless, more studies will be needed to reduce uncertainty about cause-effect relationships. - The bioaccumulation of As and Cd and signs of renal histopathological injury proved the value of Algerian mice as a bioindicator species in the risk assessment of contaminated sites.

  17. Regional hydrogen roadmap. Project development framework for the Sahara Wind Project

    Energy Technology Data Exchange (ETDEWEB)

    Benhamou, Khalid [Sahara Wind Inc., Rabat (Morocco); Arbaoui, Abdelaziz [Ecole National Superieure des Arts et Metiers ENSAM Meknes (Morocco); Loudiyi, Khalid [Al Akhawayn Univ. (Morocco); Ould Mustapha, Sidi Mohamed [Nouakchott Univ. (Mauritania). Faculte des Sciences et Techniques

    2010-07-01

    The trade winds that blow along the Atlantic coast from Morocco to Senegal represent one of the the largest and most productive wind potentials available on earth. Because of the erratic nature of winds however, wind electricity cannot be integrated locally on any significant scale, unless mechanisms are developed for storing these intermittent renewable energies. Developing distributed wind energy solutions feeding into smaller electricity markets are essential for solving energy access issues and enabling the development of a local, viable renewable energy industry. These may be critical to address the region's economic challenges currently under pressure from Sub-Saharan migrant populations. Windelectrolysis for the production of hydrogen can be used in grid stabilization, as power storage, fuel or chemical feedstock in specific industries. The objective of the NATO SfP 'Sahara Trade Winds to Hydrogen' project is to support the region's universities through an applied research framework in partnership with industries where electrolysis applications are relevant. By powering two university campuses in Morocco and Mauritania with small grid connected wind turbines and 30 kW electrolyzers generating hydrogen for power back-up as part of ''green campus concepts'' we demonstrated that wind-electrolysis for the production of hydrogen could absorb larger quantities of cheap generated wind electricity in order to maximize renewable energy uptakes within the regions weaker grid infrastructures. Creating synergies with local industries to tap into a widely available renewable energy source opens new possibilities for end users such as utilities or mining industries when processing raw minerals, whose exports generates key incomes in regions most exposed to desertification and climate change issue. Initiated by Sahara Wind Inc. a company from the private sector, along with the Al Akhawayn University, the Ecole Nationale Superieure

  18. Sahara makeup

    African Journals Online (AJOL)

    Winnie

    People living with AIDS (PWAs) are the socially weakened, whose means of survival include migrating, enduring gender violence, and they are .... for persons aged 15 - 49 in urban informal settlements can be compared with 12.1% in ..... They are the ones who today are refusing to become or remain victims of violence and ...

  19. Morphologic and structural evolution of the Algerian Margin since Messinian (-6 Myr); First results of a new experimental approach.

    Science.gov (United States)

    Dominguez, S.; Strzerzynski, P.; Déverchère, J.; Boudiaf, A.; Yelles, K.

    2009-04-01

    In the framework of the ANR (Agence Nationale de la Recherche) DANACOR Project, dedicated to the seismo-tectonic study of the Algerian Margin, we have developed an experimental approach based on a new type of analog models to investigate its morpho-structural evolution over the last 6 Myr. Present day structure of the Algerian margin results from a polyphased geologic evolution starting, during Late Oligocene, with the opening of the Western Mediterranean Sea. During lower Miocene, back-arc extension and slab roll-back, associated to the Tethyan oceanic subduction induced accretion of the Kabylian crustal blocks against the North African passive margin. At the end of Miocene, a main tectono-climatic event occurred, the Messinian salinity crisis, that left a significant footprint on the marine sedimentation and coastal morphology. Finally, during Upper Pliocene and Quaternary, due to the ongoing crustal convergence between Africa and Eurasia, the Algerian Margin experienced active compression as shown by north dipping thrusts located onland (Yelles et al., 2006) and south dipping reverse faults located at sea (Déverchère et al. 2005, Domzig et al., 2006). The occurrence of moderate to strong compressive earthquakes, such as the Boumerdes earthquake (Mw 6.9, 2003) indicates that the deformation is still active. In such a context, the objectives of our study are to evaluate the impact of the Messinian salinity crisis on the morphological and sedimentological evolution of the margin and to test different hypothesis concerning the recent compressive tectonic event that developed in the last millions years and more particularly how it affects the margin and coastal domain tectonics. To model a whole continental margin, we've modified a recent experimental technique developed initially to study the interactions between Tectonics-Erosion-Sedimentation (TES) in active mountain foreland (Graveleau and Dominguez, 2008). Erosion of emerged topographies (coastal domain) is

  20. Greening of the Sahara suppressed ENSO activity during the mid-Holocene

    Science.gov (United States)

    Pausata, Francesco S. R.; Zhang, Qiong; Muschitiello, Francesco; Lu, Zhengyao; Chafik, Léon; Niedermeyer, Eva M.; Stager, J. Curt; Cobb, Kim M.; Liu, Zhengyu

    2017-07-01

    The evolution of the El Niño-Southern Oscillation (ENSO) during the Holocene remains uncertain. In particular, a host of new paleoclimate records suggest that ENSO internal variability or other external forcings may have dwarfed the fairly modest ENSO response to precessional insolation changes simulated in climate models. Here, using fully coupled ocean-atmosphere model simulations, we show that accounting for a vegetated and less dusty Sahara during the mid-Holocene relative to preindustrial climate can reduce ENSO variability by 25%, more than twice the decrease obtained using orbital forcing alone. We identify changes in tropical Atlantic mean state and variability caused by the momentous strengthening of the West Africa Monsoon (WAM) as critical factors in amplifying ENSO's response to insolation forcing through changes in the Walker circulation. Our results thus suggest that potential changes in the WAM due to anthropogenic warming may influence ENSO variability in the future as well.

  1. Local Human Development in contexts of permanent crisis: Women’s experiences in the Western Sahara

    Directory of Open Access Journals (Sweden)

    María López Belloso

    2009-04-01

    Full Text Available Sahrawi women are active agents in the social dynamics of the refugee camps, in which they have developeda number of coping strategies to overcome the hardships of a deteriorating humanitarian situation. Since the outbreak of the con#ict and the forced settlement in Tindouf, Algeria, women have been responsible for the entire management of refugee camps, assuming leadership roles in many sectors of society.This paper highlights the Sahrawi women’s contribution to the process of local human development in a context of protracted refuge such as the one in the Western Sahara. In addition to the enlargement of the refugee population’s capacities in relation to material and physical assets, social and organizational abilities, and motivational strengths, one of the major achievements of Sahrawi women has been their own individual and collective process of empowerment within the camp life.

  2. Two cases of paradoxical hypothermia in a Sahara desert multi-stage ultramarathon

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Kaufman

    2014-11-01

    Full Text Available Exertional hypothermia in a hot environment, a seemingly contradictory state, is a clinical presentation that has not been previously described in the medical literature. We present two cases of symptomatic hypothermia of 34-35°C (95°F which resolved with ingestion of calories in otherwise healthy men competing in a multi-stage ultramarathon in the Sahara desert, Egypt 2012 with ambient temperatures of approximately 38-39°C (100- 102°F. Hypothermia is well documented in the medical literature as a presenting sign of hypoglycemia in both conscious and comatose patients. The mechanism by which hypoglycemia contributes to hypothermia is poorly understood, but may represent a compensatory response that reflects a decrease in energy demand during glucose deprivation. Wilderness medicine practitioners at endurance events should be cognizant of hypothermia as a potential presenting sign of hypoglycemia, as it can be empirically treated and rapidly reversed.

  3. Comparison of efficacy of unheated and heat-treated Sahara honey on wound healing in rabbits

    Directory of Open Access Journals (Sweden)

    Baghdad Khiati

    2015-02-01

    Full Text Available Objective: To investigate the efficacy of unheated and heat-treated Sahara honey on wound healing in rabbits on the basis of macroscopic observation changes. Methods: Eight female rabbits were used. Using aseptic surgical technique, a 3 cm incision was made on the back of each rabbit and two rabbits with injuries in each group were treated daily with a topical application of unheated and heated honey, sulfadiazine and sterile saline, respectively. Results: The unheated honey demonstrated the highest activity on the wound compared to reference ointment silver sulfadiazine, heat-treated honey and sterile saline respectively. Further the present investigation proves that unheated honey is possessing superior wound healing activity than that of heat-treated honey. Conclusions: The result of this study confirms that unheated honey had the best wound healing effect even better than heat-treated honey.

  4. Intercomparison of numerical simulations, satellite altimetry and glider observations in the Algerian Basin during fall 2014 and 2015: focus on a SARAL/AltiKa track

    Science.gov (United States)

    Aulicino, Giuseppe; Cotroneo, Yuri; Ruiz, Simon; Sanchez Roman, Antonio; Pascual, Ananda; Fusco, Giannetta; Tintoré, Joaquin; Budillon, Giorgio

    2017-04-01

    The Algerian Basin is a key-place for the study of the general circulation of the Western Mediterranean Sea and its role in reaction to climate change. The presence of both fresh Atlantic waters and more saline resident Mediterranean ones characterizes the basin with an intense inflow/outflow regime and complex circulation patterns. Very energetic mesoscale structures, that evolve from meander of the Algerian Current to isolated cyclonic and anti-cyclonic eddies, dominate the area with marked repercussions on the biological activity. Despite their remarkable importance, this region and its variability are still poorly known and basin-wide high resolution knowledge of its mesoscale and sub-mesoscale features is still incomplete. The monitoring of such complex processes requires a synergic approach that involves integrated observing systems. In recent years, several studies proved the advantages of the combined use of autonomous underwater vehicles, such as gliders, with a new generation of satellite altimeters. In this context, we present the first results of a new integrated oceanographic observing system built up in the Algerian Basin during fall 2014 and 2015, aiming at advancing our knowledge on its main features. The study was realized through the analysis of glider high resolutions three-dimensional observations, collected along the Algerian BAsin Circulation Unmanned Survey (ABACUS) monitoring line, in synergy with co-located SARAL/AltiKa altimetric products and CMEMS numerical simulations. The achieved results confirm that glider derived dynamic height and SARAL/AltiKa absolute dynamic topography present similar patterns, with RMS of the differences ranging between 1.11 and 2.90 cm. Generally, the maximum discrepancies are located nearby the Balearic Islands and the Algerian Coast, but it is important to remark that the correlation coefficients seem to mostly depend on the synopticity between in situ and satellite measurements. Still, this study confirm that

  5. Distribution of molecular breast cancer subtypes among Algerian women and correlation with clinical and tumor characteristics: a population-based study.

    Science.gov (United States)

    Cherbal, Farid; Gaceb, Hadjer; Mehemmai, Chiraz; Saiah, Insaf; Bakour, Rabah; Rouis, Abdelhalim Ould; Boualga, Kada; Benbrahim, Wassila; Mahfouf, Hassen

    2015-01-01

    Breast cancer is currently the leading cause of cancer morbidity and mortality among Algerian women. Molecular classification of breast cancer is an important factor for prognosis and clinical outcome. There are limited data regarding molecular breast cancer subtypes among Algerian women. The objective of the present study was to analyze the proportion and distribution of molecular subtypes and to determine their associations with some clinical and tumor characteristics: age at diagnosis, menopausal status, histological type and histological grade. The study population included 3014 female breast cancers. We analyzed breast cancers from cancer registries of academic medical oncology service of public hospital of Rouiba, anticancer center of Blida, and anticancer center of Batna. Breast cancers were diagnosed between 2008 and 2013. Molecular subtype classification was done based on immunohistochemical surrogates for ER (Estrogen receptor), PR (Progesterone receptor) and HER2 (human epidermal growth factor receptor-2) status obtained from medical records for 3014 breast cancer patients. Breast cancer subtypes definitions were as follow: Luminal A (ER+ and/or PR+, HER2-), Luminal B (ER+ and/or PR+, HER2+), TNBC (ER-, PR - , HER2-), HER2+ (ER-, PR-, HER2+). Molecular subtypes were correlated with the clinicopathological characteristics of the tumors. The mean age at diagnosis cancer was 48.5 years. Proportions of the luminal A, TNBC, luminal B and HER2+ breast cancer subtypes were 50.59%, 20.80%, 19.67% and 8.92%, respectively. We noted a significant difference in the distribution of age at diagnosis among the four cancer subtypes (P= 0.004). Luminal A, Luminal B, TNBC and HER2+ subtypes were significantly different by premenopausal and postmenopausal status (P= 0.01). Invasive Ductal Carcinoma was the most common histological type in all breast cancer subtypes. Tumors with histological grade 2 and 3 were more common in patients for the four breast cancer subtypes. For

  6. Inside the "African cattle complex": animal burials in the holocene central Sahara.

    Directory of Open Access Journals (Sweden)

    Savino di Lernia

    Full Text Available Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological value well beyond its mere function as 'walking larder'. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in-depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi-dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080-5120 BP or 5200-3800 BC. This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art make the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O analyses of animal remains, and botanical information are used to explore this highly formalized ritual and the lifeways of a pastoral community in the Holocene Sahara.

  7. Generation of bioethanol from common date by- products, “Teggaza ...

    African Journals Online (AJOL)

    Lenovo

    2017-01-04

    Jan 4, 2017 ... using date waste biomass abundant in Algerian Sahara. Key words: Algerian Sahara, alcoholic fermentation, bioethanol, bakery yeast, dates by-product, distillation. INTRODUCTION. Due to the variability in ... national program from 2011 to 2030 to promote concrete- actions in the fields of energy efficiency ...

  8. Greening of the Sahara - a paleo perspective on the history of water in the Middle East and North Africa

    Science.gov (United States)

    Bar-Matthews, M.

    2012-04-01

    The Middle-East, mostly at its southern edge together with North Africa, the northern edge of the Sahara Desert, are located at the boundary between high- to-mid latitude and tropical-subtropical climate systems. The geographical duality of desert adjacent to Mediterranean-type climate regions played and still plays a major role on the water availability. Thanks to the number of important paleoclimate studies that been made on accurate dating of cave speleothems in Southern Arabia and Oman (Fleitmann et al., 2011) and in the northeast Sahara, the Negev Desert Israel (Vaks et al., 2010) and the study of sapropels in Eastern and central Mediterranean (Almogi-Labin et al., 2009; Osborne et al, 2008), it is clear that the region was graced with water during peak interglacials when the African monsoon and westerly storm/rainfall systems intensified. Northward penetration of the Inter Tropical Convergence Zone over the Arabian and African continents resulted in increased discharge of the Nile River and rivers that emerged from central Sahara into the Eastern Mediterranean Sea. Correspondingly, enhanced westerly wind activity led to an increase in rainfall from Atlantic-Mediterranean sources over the entire Mediterranean basin, which even penetrated south into the north-east corner of the Sahara Desert. The Saharo-Arabian Desert became narrower and climatic "windows" opened for the dispersal of hominids and animals out of the African continent at 250-239, 210-193, 138-120, 108-98, 87-84 and 10-6.5 ka BP, with severe dry conditions in between. Greening of the Sahara Desert at these intervals is supported also by various marine and terrestrial records, such as corals, lakes, tufa deposits and archeological findings. Dry conditions prevailed in the Sahara desert during glacials. This is in contrast to the climatic conditions in the Eastern Mediterranean coastal region and the Jordan Rift Valley (Bar-Matthews et al., 2003; Lisker et al., 2010), where water was available for

  9. E-learning in engineering education: a theoretical and empirical study of the Algerian higher education institution

    Science.gov (United States)

    Benchicou, Soraya; Aichouni, Mohamed; Nehari, Driss

    2010-06-01

    Technology-mediated education or e-learning is growing globally both in scale and delivery capacity due to the large diffusion of the ubiquitous information and communication technologies (ICT) in general and the web technologies in particular. This statement has not yet been fully supported by research, especially in developing countries such as Algeria. The purpose of this paper was to identify directions for addressing the needs of academics in higher education institutions in Algeria in order to adopt the e-learning approach as a strategy to improve quality of education. The paper will report results of an empirical study that measures the readiness of the Algerian higher education institutions towards the implementation of ICT in the educational process and the attitudes of faculty members towards the application of the e-learning approach in engineering education. Three main objectives were targeted, namely: (a) to provide an initial evaluation of faculty members' attitudes and perceptions towards web-based education; (b) reporting on their perceived requirements for implementing e-learning in university courses; (c) providing an initial input for a collaborative process of developing an institutional strategy for e-learning. Statistical analysis of the survey results indicates that the Algerian higher education institution, which adopted the Licence - Master and Doctorate educational system, is facing a big challenge to take advantage of emerging technological innovations and the advent of e-learning to further develop its teaching programmes and to enhance the quality of education in engineering fields. The successful implementation of this modern approach is shown to depend largely on a set of critical success factors that would include: 1. The extent to which the institution will adopt a formal and official e-learning strategy. 2. The extent to which faculty members will adhere and adopt this strategy and develop ownership of the various measures in the

  10. A study of the relict fish fauna of northern Chad, with the first records of a polypterid and a poeciliid in the Sahara desert

    OpenAIRE

    Trape, Sébastien

    2013-01-01

    Seventeen species and sub-species of fishes belonging to four families (Cyprinidae, Clariidae, Aplocheilidae, Cichlidae) were known to occur in perennial bodies of water in the Sahara desert. The study of fishes collected in Lake Boukou near Ounianga Serir (Borkou, northern Chad) shows, for the first time, the occurrence in the Sahara desert of relict populations of Polypterus senegalus (Polypteridae) and Poropanchax normani (Poeciliidae). The Cichlidae Tilapia zilli was also collected in thi...

  11. Biogeography and conservation of mammals from the West Sahara-Sahel: an application of ecological niche-based models and GIS

    OpenAIRE

    Gomes Vale, Cândida; Campos, João C.; Silva, Teresa L.; Gonçalves, Duarte V.; Sow, Andack Saad; Martínez-Freiría, Fernando; Boratyński, Zbyszek; Brito, José Carlos

    2016-01-01

    The West Sahara-Sahel is a remote region where knowledge gaps on mammal distribution have hampered accurate local biodiversity assessments and the development of optimised conservation planning in the region. Using a geographical information system and ecological niche-based modelling tools, this study combines high resolution presence data from 22 mammals and environmental factors from the West Sahara-Sahel to identify suitable areas for mammal occurrence, biogeographic affinities among taxa...

  12. Geochemical and mineralogical evidence for Sahara and Sahel dust additions to Quaternary soils on Lanzarote, eastern Canary Islands, Spain

    Science.gov (United States)

    Muhs, D.R.; Budahn, J.; Skipp, G.; Prospero, J.M.; Patterson, D.; Bettis, E. Arthur

    2010-01-01

    Africa is the most important source of dust in the world today, and dust storms are frequent on the nearby Canary Islands. Previous workers have inferred that the Sahara is the most important source of dust to Canary Islands soils, with little contribution from the Sahel region. Soils overlying a late Quaternary basalt flow on Lanzarote, Canary Islands, contain, in addition to volcanic minerals, quartz and mica, exotic to the island's bedrock. Kaolinite in the soils also likely has an exotic origin. Trace-element geochemistry shows that the soils are derived from varying proportions of locally derived basalt and African dust. Major-element geochemistry, clay mineralogy and interpretation of satellite imagery suggest that dust additions to the Canary Islands come not only from the Sahara Desert, but also from the Sahel region. ?? Published 2010. This article is a US Government work and is in the public domain in the USA.

  13. 1H NMR based metabolic profiling of eleven Algerian aromatic plants and evaluation of their antioxidant and cytotoxic properties.

    Science.gov (United States)

    Brahmi, Nabila; Scognamiglio, Monica; Pacifico, Severina; Mekhoukhe, Aida; Madani, Khodir; Fiorentino, Antonio; Monaco, Pietro

    2015-10-01

    Eleven Algerian medicinal and aromatic plants (Aloysia triphylla, Apium graveolens, Coriandrum sativum, Laurus nobilis, Lavandula officinalis, Marrubium vulgare, Mentha spicata, Inula viscosa, Petroselinum crispum, Salvia officinalis, and Thymus vulgaris) were selected and their hydroalcoholic extracts were screened for their antiradical and antioxidant properties in cell-free systems. In order to identify the main metabolites constituting the extracts, 1 H NMR-based metabolic profiling was applied. Data obtained emphasized the antiradical properties of T. vulgaris, M. spicata and L. nobilis extracts (RACI 1.37, 0.97 and 0.93, respectively), whereas parsley was the less active as antioxidant (RACI -1.26). When the cytotoxic effects of low and antioxidant doses of each extract were evaluated towards SK-N-BE(2)C neuronal and HepG2 hepatic cell lines, it was observed that all the extracts weakly affected the metabolic redox activity of the tested cell lines. Overall, data strongly plead in favor of the use of these plants as potential food additives in replacement of synthetic compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Effect of Spanish style processing on the phenolic compounds and antioxidant activity of Algerian green table olives

    Energy Technology Data Exchange (ETDEWEB)

    Mettouchi, S.; Sacchi, R.; Ould Moussa, Z.E.D.; Paduano, A.; Savarese, M.; Tamendjari, A.

    2016-07-01

    The study was carried out on seven Algerian olive cultivars to report the effect of Spanish style processing on individual and total phenolic compounds and the changes that occur in antioxidant capacity. The results indicate that the treatment leads to losses in phenolic contents which are cultivar dependent. Sigoise is the least affected variety (12.25%) and Azzeradj from Seddouk the most affected one (94.80%). The phenolic profile shows drastic changes after processing. Hydroxytyrosol is dominant in processed olives (14.42–545.42 mg·100 g−1) while oleuropein is the major phenolic compound in fresh olives (994.27 mg·100 g−1). As a consequence to the loss in phenolic content, substantial reductions in the antioxidant activities of the extracts are noted. They are estimated to be 13.12–92.75% in scavenging activity against the DPPH radical, 37.78–93.98% in reducing capacity, 59.45–97.94% in the hydrogen peroxide radical and 7.26–51.66% in the inhibition bleaching of β-carotene. Among the processed varieties, only Sigoise presented a positive value of RACI (relative antioxidant capacity index). (Author)

  15. Effectiveness of convective drying to conserve indigenous yeasts with high volatile profile isolated from algerian fermented raw bovine milk (Rayeb

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    Latifa HAMOUDI-BELARBI

    2016-01-01

    Full Text Available Abstract Yeasts Candida tropicalis, Yarrowia lipolytica, Wickerhamomyces anomalus, Issatchenkia orientalis, Kluyveromyces marxianus, Saprochaete suaveolens and Trichosporon coremiiforme were isolated and identified by physiological, biochemical tests with API 20C AUX system and molecular methods by restriction fragment analysis of PCR-amplified 28S-rRNA from Algerian fermented raw bovine milk (Rayeb. Selected yeasts S. suaveolens, I. orientalis, K. marxianus and W. anomalus produced esters and higher esters which can exert a pertinent influence on the sensory characteristics of Rayeb. Viability of S. suaveolens and W. anomalus using three methods of drying (freeze-drying, convective drying, and spray-drying and during 4 months of storage at 4 °C and 25 °C in the darkness was studied. Immediately after each drying method, high survival was obtained using freeze-drying followed by convective drying in rice cakes and spray-drying respectively. During storage at 4 °C, convective drying provided better survival of yeast cultures of S. suaveolens and W. anomalus than freeze-drying. At 25 °C of storage, convective and freeze-dried yeast cultures showed no significant loss of viable cells up to 2 months of storage. Spray-dried yeast cultures had the greatest loss of viable count during the 3 months of storage at 25 °C.

  16. Estimation of canine Leishmania infection prevalence in six cities of the Algerian littoral zone using a Bayesian approach.

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    Amel Adel

    Full Text Available A large-scale study on canine Leishmania infection (CanL was conducted in six localities along a west-east transect in the Algerian littoral zone (Tlemcen, Mostaganem, Tipaza, Boumerdes, Bejaia, Jijel and covering two sampling periods. In total 2,184 dogs were tested with an indirect fluorescent antibody test (IFAT and a direct agglutination test (DAT. Combined multiple-testing and several statistical methods were compared to estimate the CanL true prevalence and tests characteristics (sensitivity and specificity. The Bayesian full model showed the best fit and yielded prevalence estimates between 11% (Mostaganem, first period and 38% (Bejaia, second period. Sensitivity of IFAT varied (in function of locality between 86% and 88% while its specificity varied between 65% and 87%. DAT was less sensitive than IFAT but showed a higher specificity (between 80% and 95% in function of locality or/and season. A general increasing trend of the CanL prevalence was noted from west to east. A concordance between the present results and the incidence of human cases of visceral leishmaniasis was observed, where also a maximum was recorded for Bejaia. The results of the present study highlight the dangers when using IFAT as a gold standard.

  17. The p19 protein of Grapevine Algerian latent virus is a determinant of systemic infection of Chenopodium quinoa.

    Science.gov (United States)

    Kim, Semin; Cho, Won Kyong; Lee, Hyeok-Geun; Park, Sang-Ho; Sohn, Seong-Han; Kim, Kook-Hyung

    2012-04-01

    A previous study showed that both Grapevine Algerian latent virus (GALV) and Tomato bushy stunt virus (TBSV) systemically infect Nicotiana benthamiana, but GALV causes systemic infection whereas TBSV causes only local lesions in Chenopodium quinoa (C. quinoa). We recently isolated GALV strain Naju (GALV-N) from Limonium sinense and TBSV strain Sacheon (TBSV-S) from tomato. Both viruses belong to the genus Tombusvirus and have a similar genome organization. To identify determinants of systemic infection of GALV-N in C. quinoa in the current study, we generated infectious clones and capsid protein (CP)-deletion clones for the two viruses and confirmed that CP of GALV-N is required for systemic infection of C. quinoa due to its primary structural role in virus assembly. Through the use of chimeras, we identified a viral factor in addition to CP that contributes to systemic infection by GALV-N. Inactivation of the p19 demonstrated that host-specific activities of p19 are necessary for efficient systemic infection of C. quinoa by GALV-N. Our study is the first report to determine the viral factors required for systemic infection of GALV in C. quinoa. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Characterization of sterolic and alcoholic fractions of some Algerian olive oils according to the variety and ripening stage

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    Boulkroune Hasna

    2017-09-01

    Full Text Available The present study reported for the first time the evolution of some minor compounds (sterols and aliphatic alcohols composition of four Algerian olive oils according to the cultivar and the maturity stage during the season (2013/2014. Olive samples were collected during eight different harvesting dates. The studied cultivars were Chemlal, Aghenfas, Buichret and Mekki. Ten sterolic compounds, triterpene dialcohols (erythrodiol + uvaol and seven fatty alcohols were identified and characterized. The results showed a decreasing level of total sterols, β-sitosterol, triterpenic dialcohols, total aliphatic alcohols, tetracosanol (C24, and an increasing level of Δ5-avenasterol according to the maturity process. Linear discriminant analysis (LDA enabled the classification of the studied varieties on the basis of analytical data and a correct classification rate of 96.5% and 88.6% was achieved using the original and cross validation method respectively. The most discriminating variables have been: cholesterol, campestanol, Δ7-stigmastenol, Δ7-avenasterol, clerosterol, alcohol C22, alcohol C25, alcohol C27.

  19. Multiresistant opportunistic pathogenic bacteria isolated from polluted rivers and first detection of nontuberculous mycobacteria in the Algerian aquatic environment.

    Science.gov (United States)

    Djouadi, Lydia Neïla; Selama, Okba; Abderrahmani, Ahmed; Bouanane-Darenfed, Amel; Abdellaziz, Lamia; Amziane, Meriam; Fardeau, Marie-Laure; Nateche, Farida

    2017-08-01

    Opportunistic infections constitute a major challenge for modern medicine mainly because the involved bacteria are usually multiresistant to antibiotics. Most of these bacteria possess remarkable ability to adapt to various ecosystems, including those exposed to anthropogenic activities. This study isolated and identified 21 multiresistant opportunistic bacteria from two polluted rivers, located in Algiers. Cadmium, lead, and copper concentrations were determined for both water samples to evaluate heavy metal pollution. High prevalence of Enterobacteria and non-fermentative Gram-negative rods was found and a nontuberculous Mycobacterium (NTM) strain was isolated. To the best of our knowledge, this is the first detection of NTM in the Algerian environment. The strains were tested for their resistance against 34 antibiotics and 8 heavy metals. Multiple antibiotics and heavy metals resistance was observed in all isolates. The two most resistant strains, identified as Acinetobacter sp. and Citrobacter freundii, were submitted to plasmid curing to determine if resistance genes were plasmid or chromosome encoded. Citrobacter freundii strain P18 showed a high molecular weight plasmid which seems to code for resistance to zinc, lead, and tetracycline, at the same time. These findings strongly suggest that anthropized environments constitute a reservoir for multiresistant opportunistic bacteria and for circulating resistance genes.

  20. Viruses in the desert: a metagenomic survey of viral communities in four perennial ponds of the Mauritanian Sahara

    OpenAIRE

    Fancello, Laura; Trape, S?batien; Robert, Catherine; Boyer, Micka?l; Popgeorgiev, Nikolay; Raoult, Didier; Desnues, Christelle

    2012-01-01

    Here, we present the first metagenomic study of viral communities from four perennial ponds (gueltas) located in the central Sahara (Mauritania). Three of the four gueltas (Ilij, Molomhar and Hamdoun) are located at the source of three different wadis belonging to the same hydrologic basin, whereas the fourth (El Berbera) belongs to a different basin. Overall, sequences belonging to tailed bacteriophages were the most abundant in all four metagenomes although electron microscopy and sequencin...

  1. Micro—Raman Spectroscopy of Diamonds from JaH 054 and Sahara 98505 Ureilites, Statistic Research

    Science.gov (United States)

    Karczemska, A.; Jakubowski, T.; Kozanecki, M.; Tszydel, I.; Jauss, A.; Gucsik, A.

    2009-08-01

    In this paper Raman spectra of diamonds from two different ureilites, JaH 054 and Sahara 98505, were measured. Obtained results for both ureilites showed the Raman shift ranged between 1321 cm-1 and 1336 cm-1 for JaH 054 and between 1329 cm-1 and 1336 cm-1 for Sahara 98505. FWHM parameter (full width at half maximum) varied also in wide range especially for Sahara 98505. Raman imaging was done for JaH 054 sample and diamonds of different Raman shifts (1321 cm-1, 1328 cm-1, 1330 cm-1) were found in few tens μm sized area of carbon vein. Raman peaks of ureilitic diamonds were compared with literature data of laboratory diamonds produced under high pressure, under low pressure with MW PACVD method and with other ureilites. Presented research showed that even in highly shocked ureilites Raman shift versus FWHM parameter plots are similar with CVD diamonds for ureilites. However, the origin of diamonds in ureilites is not explained based on the obtained results, close coexistence of different diamonds in investigated ureilites suggests that the mechanism of diamond creation in meteorites was very complex and could be multi-step process.

  2. Lake Yoa (Northern Chad): A Seasonal Footprint of 10,500 Years of Climate Change in the Sahara

    Science.gov (United States)

    Kroepelin, S.; Cocquyt, C.; Darius, F.; Dinies, M.; Francus, P.; Just, J.; Karls, J.; Kuper, J.; Lézine, A. M.; Mallaye, B.; Melles, M.; Sylvestre, F.; Viehberg, F. A.; Wennrich, V.

    2016-12-01

    We present Africa's most complete Holocene climate record in a long awaited breakthrough that few would have expected in one of the driest and most remote parts of the Sahara, the planet's major hot desert. A 16 m thick continuous sequence of seasonally laminated (varved) deposits at the bottom of a now fully groundwater-supported oasis lake at Ounianga Kebir in northern Chad extends our earlier 6,000 year record published in 2008 back to the onset of postglacial humid conditions 10,500 years ago in unrivalled detail. Main results indicate a rather slow regreening in northern Africa after 100,000 years of apparently continuous late Pleistocene aridity; precisely define the severe environmental impact of global climate events such as the 8,200 BP North Atlantic cooling even in hypercontinental positions far away from the oceans; and corroborate the gradual termination of the last "Green Sahara" period over millennia. Lake Yoa's varve count-controlled age model also shows the high error potential of the existing 14C chronology from bulk carbonate-dated paleolacustrine archives elsewhere in the Sahara and provides a basis for its correction. The new terrestrial multiproxy data set discloses agreements and discrepancies to marine and ice core data, and numeric climate models. As a natural analogue, it helps to foresee how North Africa's climate and environments might evolve due to anthropogenic global warming.

  3. Crater palaeolakes in the Tibesti mountains (Central Sahara, North Chad) - New insights into past Saharan climates

    Science.gov (United States)

    Kröpelin, Stefan; Dinies, Michèle; Sylvestre, Florence; Hoelzmann, Philipp

    2016-04-01

    For the first time continuous lacustrine sections were sampled from the volcanic Tibesti Mountains (Chad): In the 900 m deep crater of Trou au Natron at Pic Toussidé (3,315 m a.s.l.) and from the 800 m deep Era Kohor, the major sub-caldera of Emi Koussi (3,445 m a.s.l.). The remnant diatomites on their slopes are located 360 m (Trou au Natron) and 125 m (Era Kohor) above the present day bottom of the calderas. These sediments from highly continental positions in the central Sahara are keys for the reconstruction of the last climatic cycles (Kröpelin et al. 2015). We report first results from sedimentary-geochemical (total organic and total inorganic carbon contents; total nitrogen; major elements; mineralogy) and palynological analyses for palaeo-environmental interpretations. The diatomites from the Trou au Natron comprise 330 cm of mostly calcitic sediments with relatively low organic carbon (moss/fern stands. Regional pollen rain-e.g. grasses and wormwood-is scarcely represented. Golden algae dominate in the lower section. The results of the first palynological samples suggest a small sedimentation basin. Two 14C-dated charcoals out of the upper part of the section indicate mid-Holocene ages and a linear extrapolation based on a sediment accumulation rate of 1.4mma-1 would lead to tentative dates of ~8650 cal a BP for basal lacustrine sediments and ~4450 cal a BP for the cessation of this lacustrine sequence. The diatomites from the Era Kohor reflect a suite of sections that in total sum up to 145 cm of mostly silica-based sediments with very low carbon contents (flora mainly composed of benthic and tychoplanktonic species, indicating a shallow freshwater lake. Both diatomite sequences thus suggest shallow lakes throughout their deposition-whether this is due to their marginal position within the large calderas and/or shallow waters covered the entire calderas is an outstanding question that will be addressed with planned additional investigations. Kr

  4. Sahara dust, ocean spray, volcanoes, biomass burning: pathways of nutrients into Andean rainforests

    Science.gov (United States)

    Fabian, P.; Rollenbeck, R.; Spichtinger, N.; Brothers, L.; Dominguez, G.; Thiemens, M.

    2009-10-01

    Regular rain and fogwater sampling in the Podocarpus National Park, on the humid eastern slopes of the Ecuadorian Andes, along an altitude profile between 1960 and 3180 m, has been carried out since 2002. The samples, accumulated over about 1-week intervals, were analysed for pH, conductivity and major ions (K+, Na+, NH4+, Ca2+, Mg2+, Cl-, SO42-, NO3-, PO43-). About 35% of the weekly samples had very low ion contents, with pH mostly above 5 and conductivity below 10 μS/cm. 10-days back trajectories (FLEXTRA) showed that respective air masses originated in pristine continental areas, with little or no obvious pollution sources. About 65%, however, were significantly loaded with cations and anions, with pH as low as 3.5 to 4.0 and conductivity up to 50 μS/cm. The corresponding back trajectories clearly showed that air masses had passed over areas of intense biomass burning, active volcanoes, and the ocean, with episodic Sahara and/or Namib desert dust interference. Enhanced SO42- and NO3+ were identified, by combining satellite-based fire pixel observations with back trajectories, as predominantly resulting from biomass burning. Analyses of oxygen isotopes 16O, 17O, and 18O in nitrate show that nitrate in the samples is indeed a product of atmospheric conversion of precursors. Some SO42-, about 10% of the total input, could be identified to originate from active volcanoes, whose plumes were encountered by about 10% of all trajectories. Enhanced Na+, K+, and Cl- were found to originate from ocean spray sources. They were associated with winds providing Atlantic air masses to the receptor site within less than 5 days. Episodes of enhanced Ca2+ and Mg2+ were found to be associated with air masses from African deserts. Satellite aerosol data confirm desert sources both on the Northern (Sahara) as on the Southern Hemisphere (Namib), depending on the season. A few significant PO43- peaks are related with air masses originating from North African phosphate mining fields.

  5. Impact of Prolonged Periods Classroom Settings in Intra-abdominal fat area and its Consequence on Posture/Balance Control among Algerian Childhood College Preparatory School.

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    Zerf Mohammed

    2017-08-01

    Full Text Available The play has been shown to help children adjust to the school setting and to enhance children's learning [1]. Since this theory, the current study was designed to examine the significance of mechanical effects of intra-abdominal on posture/balance control among the Algerian Childhood Primary Schools. Since our teachers emphasise the good classroom settings as a discipline pedagogical aspect of success learning. While High-quality educational programs for children in preschool and kindergarten have play at the centre of the curriculum [2]. Our interventions in this study aimed to examine Impact of Prolonged Periods Classroom Settings in Intra-abdominal fat area and its Consequence on Posture/Balance Control among Algerian Childhood Preparatory Schools. for the purpose, a total of 61 schoolboys of Slimane provinces Naama, Municipality Mecheria, Algeria male gender their average age 5±1.52 years distributed into two homogeneous groups, according to them, school attendance (kindergarten School (29 boys - preschool (32 boys. Tested by saving tests (Body Fat Percentage-Abdominal circumference - Modified Bass Test of Dynamic Balance and standing balance. Based on the analysis statistics, we confirm: • Prolonged periods classroom settings increase Intra-Abdominal Fat which represents big risk posture/balance control. • Primary schools posture needs an interactive play method Learning classroom to improve body imbalance as health benefits physical activities. Based on the differences acquired by the research team, we emphasise that prolonged periods classroom settings Primary Schools increase the intra-abdominal which owing to the weakness of skeletal muscle fatigue and abnormal pathological alignment. While as a recommendation pedagogy practised, we suggested to our teachers, who work with these children to know that the balanced posture requires more energy in the class, Considering that our student seat more than 6 hours a day, 30 per week, and

  6. NWA 1152 and Sahara 00182: New primitive carbonaceous chondrites with affinities to the CR and CV groups

    Science.gov (United States)

    Smith, Caroline L.; Russell, Sara S.; Gounelle, Matthieu; Greenwood, Richard C.; Franchi, Ian A.

    2004-12-01

    We have investigated the mineralogy, petrography, bulk chemistry, and light element isotope composition of the ungrouped chondrites North West Africa (NWA) 1152 and Sahara 00182. NWA 1152 contains predominantly type 1 porphyritic olivine (PO) and porphyritic olivine-pyroxene (POP) chondrules. Chondrule silicates are magnesium-rich (Fo98.8 +/- 1.2, n = 36; Fs2.3 +/- 2.1 Wo1.2 +/- 0.3, n = 23). Matrix comprises ~40 vol% of the sample and is composed of a micron sized silicate groundmass with larger silicate, sulfide, magnetite, and Fe-Ni metal (Ni ~50 wt%) grains. Phyllosilicates were not observed in the matrix. Refractory inclusions are rare (0.3 vol%) and are spinel pyroxene aggregates or amoeboid olivine aggregates; melilite is absent from the refractory inclusions. Sahara 00182 contains predominantly type 1 PO chondrules, POP chondrules are less common. Most chondrules contain blebs of, and are often rimmed with, Fe-Ni metal and sulfide. Chondrule phenocrysts are magnesium-rich (Fo92.2 +/- 0.6, n = 129; Fs4.4 +/- 1.8 Wo1.3 +/- 1.1, n = 16). Matrix comprises ~30 vol% of the meteorite and is predominantly sub-micron silicates, with rare larger silicate gains. Matrix Fe-Ni metal (mean Ni = 5.8 wt%) and sulfide grains are up to mm scale. No phyllosilicates were observed in the matrix. Refractory inclusions are rare (1.1 vol%) and melilite is absent. The oxygen isotope composition of NWA 1152 falls within the range of the CV chondrites with ?17O = ?3.43? ?18O = 0.70? and is similar to Sahara 00182, ?17O = ?3.89?, ?18O = ?0.19? (Grossman and Zipfel 2001). Based on mineralogical and petrographic characteristics, we suggest NWA 1152 and Sahara 00182 show many similarities with the CR chondrites, however, oxygen isotopes suggest affinity with the CVs. Thus, neither sample can be assigned to any of the currently known carbonaceous chondrite groups based on traditionally recognized characteristics. Both samples demonstrate the complexity of inter- and intra

  7. Trapping or tethering stones (TS: A multifunctional device in the Pastoral Neolithic of the Sahara.

    Directory of Open Access Journals (Sweden)

    Marina Gallinaro

    Full Text Available The Pierres de Ben Barour, also known as trapping or tethering stones (TS, are stone artefacts with notches or grooves usually interpreted as hunting devices on the basis of rock art engravings. Though their presence is a peculiar feature of desert landscapes from the Sahara to the Arabian Peninsula, we know little about their age, context and function. Here we present a new approach to the study of these artefacts based on a large dataset (837 items recorded in the Messak plateau (SW Libya. A statistically-based geoarchaeological survey carried out between 2007 and 2011 in Libya, alongside landscape and intra-site analyses of specific archaeological features (such as rock art, settlement and ceremonial contexts, reveal that these artefacts were used for a prolonged period, probably from the early Holocene. This was followed by a multifunctional use of these devices, particularly during the Pastoral Neolithic phase (ca. 6400-3000 cal BC, with the highest concentrations being found near ceremonial contexts related to cattle burials.

  8. Model Simulations of Complex Dust Emissions over the Sahara during the West African Monsoon Onset

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    Carolina Cavazos-Guerra

    2012-01-01

    Full Text Available The existing limitations in ground-based observations in remote areas in West Africa determine the dependence on numerical models to represent the atmospheric mechanisms that contribute to dust outbreaks at different space-time scales. In this work, the ability of the Weather Research and Forecasting model coupled with the Chemistry (WRF-Chem model using the GOCART dust scheme is evaluated. The period comprises the West African Monsoon onset phase (the 7th to 12th of June, 2006 coinciding with the AMMA Special Observing Period (SOP. Different features in the horizontal and vertical dynamical structure of the Saharan atmosphere are analyzed with a combination of satellite and ground-based observations and model experimentation at 10 and 30 km model resolution. The main features of key Saharan dust processes during summer are identifiable, and WRF-CHEM replicates these adequately. Observations and model analyses have shown that cold pools (haboobs contributed a substantial proportion of total dust during the study period. The comparative analysis between observations and WRF-Chem simulations demonstrates the model efficiency to simulate the spatial and 3D structure of dust transport over the Sahara and Sahel. There is, therefore, a strong basis for accurate forecasting of dust events associated with synoptic scale events when model dust emission parameterization is suitably calibrated.

  9. The Right to Self-Determination and Natural Resources: The Case of Western Sahara

    Directory of Open Access Journals (Sweden)

    Hans Morten Haugen

    2007-06-01

    Full Text Available Phosphate, fish and possibly oil and gas all constitute important natural resources found on the territory and in the waters of Western Sahara. The importance of these natural resources must be recognised in order to understand the stalemate in the attempted process of decolonisation from Morocco which has been going on for more than 30 years. The article analyses the ‘resource dimension’ of the right to self-determination, as recognised in human rights treaties and in Resolution III of the UN Conference on the Law of the Seas, as well as several resolutions from the United Nations General Assembly. If the resources are exploited in a manner which does not benefit the peoples seeking to enjoy the right to self-determination, such exploitation is illegal. The article shows that the current exploitation takes place in a manner contrary to the interests of the local population, the Saharawis. The article also demonstrates that recent license agreements with Saharawi authorities in the field of oil and gas, signal a potentially new and constructive approach by international corporations.

  10. Bacterial composition and survival on Sahara dust particles transported to the European Alps

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    Marco eMeola

    2015-12-01

    Full Text Available Deposition of Sahara dust (SD particles is a frequent phenomenon in Europe, but little is known about the viability and composition of the bacterial community transported with SD. The goal of this study was to characterize SD-associated bacteria transported to the European Alps, deposited and entrapped in snow. During two distinct events in February and May 2014, SD particles were deposited and promptly covered by falling snow, thus preserving them in distinct ochre layers within the snowpack. In June 2014, we collected samples at different depths from a snow profile at the Jungfraujoch (Swiss Alps; 3621 m a.s.l.. After filtration, we performed various microbiological and physicochemical analyses of the snow and dust particles therein that originated in Algeria.Our results show that bacteria survive and are metabolically active after the transport to the European Alps. Using high throughput sequencing, we observed distinct differences in bacterial community composition and structure in SD-layers as compared to clean snow layers. Sporulating bacteria were not enriched in the SD-layers; however, phyla with low abundance such as Gemmatimonadetes and Deinococcus-Thermus appeared to be specific bio-indicators for SD. Since many members of these phyla are known to be adapted to arid oligotrophic environments and UV radiation, they are well suited to survive the harsh conditions of long-range airborne transport.

  11. Oxygen isotopic composition of fulgurites from the Egyptian Sahara and other locations.

    Science.gov (United States)

    Longinelli, Antonio; Serra, Romano; Sighinolfi, Giampaolo; Selmo, Enricomaria; Sgavetti, Maria

    2012-09-15

    Fulgurites are glassy crusts or hollow glassy tubes formed by the impact of a lightning strike on a target material on the Earth's surface. The oxygen isotopic composition of fulgurites has never been measured and, consequently, it is unknown whether or not isotopic fractionations take place between the target material and the fulgurite glass during the lightning event which is an excellent natural example of extremely fast melting process. Following well-established procedures (high-temperature reaction of the fulgurite material with BrF(5), conversion into CO(2) of the evolved O(2) and measurement of the(18)O/(16)O ratio on a Finnigan Delta S mass spectrometer) we measured for the first time the oxygen isotopic composition of sets of fulgurites coming from various locations on the Earth's surface. The range of isotopic values is quite large, probably reflecting the oxygen isotopic values of the target materials. In the case of fulgurites from the Sahara Desert the isotopic values obtained from the bulk material, quartz crystals sticking to the fulgurite body, tiny samples of loose sand coming from fulgurite bubbles, and sand samples collected near the fulgurites, are very close to one another. Although we do not have indisputable evidence, we conclude that, at least in the case of oxygen, the fusion process of the material struck by lightning, as well as all the extremely fast high-temperature fusion processes, probably take place without any isotopic fractionation effect. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Algerian propolis extracts: Chemical composition, bactericidal activity and in vitro effects on gilthead seabream innate immune responses.

    Science.gov (United States)

    Soltani, El-Khamsa; Cerezuela, Rebeca; Charef, Noureddine; Mezaache-Aichour, Samia; Esteban, Maria Angeles; Zerroug, Mohamed Mihoub

    2017-03-01

    Propolis has been used as a medicinal agent for centuries. The chemical composition of four propolis samples collected from four locations of the Sétif region, Algeria, using gas chromatography-mass spectrometry was determined. More than 20 compounds and from 30 to 35 compounds were identified in the aqueous and ethanolic extracts, respectively. Furthermore, the antimicrobial activity of the propolis extracts against two marine pathogenic bacteria was evaluated. Finally, the in vitro effects of propolis on gilthead seabream (Sparus aurata L.) leucocyte activities were measured. The bactericidal activity of ethanolic extracts was very high against Shewanella putrefaciens, average against Photobacterium damselae and very low against Vibrio harveyi. The lowest bactericidal activity was always that found for the aqueous extracts. When the viability of gilthead seabream head-kidney leucocytes was measured after 30 min' incubation with the different extracts, both the ethanolic and aqueous extracts of one of the propolis samples (from Babor) and the aqueous extract of another (from Ain-Abbassa) provoked a significant decrease in cell viability when used at concentrations of 100 and 200 μg ml -1 . Furthermore, significant inhibitory effects were recorded on leucocyte respiratory burst activity when isolated leucocytes where preincubated with the extracts. This effect was dose-dependent in all cases except when extracts from a third propolis sample (from Boutaleb) were used. Our findings suggest that some of Algerian propolis extracts have bactericidal activity against important bacterial pathogens in seabream and significantly modulate in vitro leucocyte activities, confirming their potential as a source of new natural biocides and/or immunomodulators in aquaculture practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Comparative assessment of HPV, alcohol and tobacco etiological fractions in Algerian patients with laryngeal squamous cell carcinoma.

    Science.gov (United States)

    Kariche, Nora; Hortal, Montserrat Torres; Benyahia, Samir; Alemany, Laia; Moulaï, Nabila; Clavero, Omar; Muñoz, Marleny; Ouahioune, Wahiba; Djennaoui, Djamel; Touil-Boukoffa, Chafia; de Sanjosé, Silvia; Bourouba, Mehdi

    2018-01-01

    Despite the increasing incidence of laryngeal squamous cell carcinoma (LSCC) in Algeria, scarce information is available on the importance of the preventable etiological factors which may drive the disease. Remarkably, a significant number of cases occur in nonsmoker and nondrinker patients; hence, suggesting that alternative risk factors, like Human papillomavirus (HPV), might be etiologically involved. To gain more insight on the risk factors associated with the disease in the country, we evaluated the etiological fraction of HPV in comparison to tobacco and alcohol intake in LSCC patients. To evaluate the etiopathologic fraction (EF) for HPV compared to history of tobacco and alcohol in LSCC, HPV DNA presence in 46 invasive and 3 non-invasive formalin-fixed paraffin-embedded laryngeal tumors was screened using the SPF10-DEIA-LiPA25 Assay. Demographic data and information related to exposure to the risk factors were gathered through interviewer-assisted questionnaires. We observed that 40.8% of all LSCC cases were associated with smoking, 40.8% had combined tobacco and alcohol exposure history, and 14.3% did not show prior exposure to either risk factor. 1 out of 3 in-situ carcinoma cases was positive for HPV-6. HPV prevalence was null in the invasive tumors. HPV DNA was detected in 2.38% for all studied cases. 10.2% of LSCC patients did not associate with any of the studied risk factors. Here we show that HPV etiological fraction in LSCC Algerian patients is low and smoking and alcohol remain the principal etiopathologic risk for LSCC burden in Algeria.

  14. Correlation between Body Condition Score, Blood Biochemical Metabolites, Milk Yield and Quality in Algerian Montbéliarde Cattle

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    Charef-Eddine Mouffok1,2,*, Toufik Madani1,2, Lounis Semara1, Nadhira Ayache1 and Amina Rahal1

    2013-04-01

    Full Text Available This study aimed to investigate the correlation between body condition score (BCS, blood biochemical metabolites, milk yield (MY and quality (Mfat in Montbéliarde cattle (31 cows reared in 5 farms of Algerian semi arid area. The BCS was measured in dry and peak of lactation (6 weeks after calving. Blood samples were taken at the time of body condition (BC measurement for determination of energy (Glucose, cholesterol, triglycerides and B-Hydroxybutyrate, nitrogen (urea and albumin and mineral (calcium metabolites. Milk yield was recorded in the 6th week of lactation (peak. A sample of milk for each cow was used to determinate milk fat, density and acidity. The results showed a significant decrease in postpartum BCS accompanied by an increase in cholesterol and B-Hydroxybutyrate (BHB concentration. The correlation analysis showed that BHB concentration in pre calving was negatively correlated with BCS (r=-0.321; P<0.05 and cholesterol (r=-0.308; P<0.05. In postpartum, BCS was negatively correlated with cholesterol (r=-0.416; P<0.05, urea (r=-0.366; P<0.05 and BHB (r=-0.487; P<0.05. However, the level of milk production decreased significantly with high glucose (r=-0.449; P<0.05 and BHB (r=-0.514; P<0.05. The fat content increased significantly with blood triglycerides (r=0.681; P<0.05 and BHB (r=0.522; P<0.05 concentration, indicating a high mobilization of body reserves used for the synthesis of milk fat. In conclusion, it can be assumed that the rate of BHB seems to be the best indicator of the nutritional status of dairy cows that determines their production level and quality.

  15. Selective Synthesis, Characterization and Kinetics Studies of poly(α-Methyl styrene induced by Maghnite-Na+ Clay (Algerian MMT

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    Moulkheir Ayat

    2016-10-01

    Full Text Available A new and efficient catalyst of Na-Montmorillonite (Na+-MMT was employed in this paper for α-methylstyrene (AMS cationic polymerization. Maghnite clay, obtained from Tlemcen Algeria, was investigated to remove heavy metal ion from wastewater. “Maghnite-Na” is a Montmorillonite sheet silicate clay, exchanged with sodium as an efficient catalyst for cationic polymerization of many vinylic and heterocyclic monomers. The various techniques, including 1H-NMR, 13C-NMR, IR, DSC and Ubbelohde viscometer, were used to elucidate structural characteristics and thermal properties of the resulting polymers. The structure compositions of “MMT”, “H+-MMT” and “Na+-MMT” have been developed. It was found that the cationic polymerization of AMS is initiated by Na+-MMT at 0 °C in bulk and in solution. The influences of reaction temperature, solvent, weight ratio of initiator/monomer and reaction time on the yield of monomer and the molecular weight are investigated. The kinetics indicated that the polymerization rate is first order with respect to the monomer concentration. A possible mechanism of this cationic polymerization is discussed based on the results of the 1H-NMR Spectroscopic analysis of these model reactions. A cationic mechanism for the reaction was proposed. From the mechanism studies, it was showed that monomer was inserted into the growing chains. Copyright © 2016 BCREC GROUP. All rights reserved. Received: 6th September 2016; Revised: 27th April 2016; Accepted: 7th June 2016 How to Cite: Ayat, M., Belbachir, M., Rahmouni, A. (2016. Selective Synthesis, Characterization and Kinetics Studies of poly(α-Methyl styrene induced by Maghnite-Na+ Clay (Algerian MMT. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (3: 376-388 (doi:10.9767/bcrec.11.3.578.376-388 Permalink/DOI: http://doi.org/10.9767/bcrec.11.3.578.376-388

  16. Spatial, temporal and ontogenetic variation in diet of anchovy ( Engraulis encrasicolus) on the Algerian coast (SW Mediterranean)

    Science.gov (United States)

    Bacha, M.; Amara, R.

    2009-11-01

    The diet of anchovy Engraulis encrasicolus was studied in three regions (Béjaia, Bénisaf and Ghazaouet) along the Algerian coast. Ontogenetic, spatial and seasonal variations in anchovy diet were investigated using multivariate analyses and analysed in relation with sea surface temperature and chlorophyll- a. 46 prey taxa of varying size between 0.57 mm ( Euterpina acutifrons) and 6.8 mm (fish larvae) were recorded. Whatever the season, the region or the fish size, anchovy is exclusively zooplanktivorous and copepods were the most present prey, constituting 87% by number of the prey taken and found in 98% of the anchovy stomachs examined. However, their occurrence and number varied according to the different areas, seasons and fish size. During its first year of life, anchovy feeds almost exclusively on copepods (mainly small and medium size prey). As anchovy grows, copepods are gradually substituted by large crustaceans such as decapods and amphipods. Hierarchical cluster analysis, analysis of similarities (ANOSIM) and similarities percentage (SIMPER) indicated a distinct diet of anchovy of the bay of Bejaia from those of the bays of Bénisaf and Ghazaouet probably due to differences in hydrologic conditions. Diet differences also occurred between seasons. Summer and spring have distinct prey assemblages each and showed low diet similarities with the two other seasons. More prey species were found in the diet during winter (36) and autumn (30) and the vacuity index was lower in winter. Temporal variability in satellite-derived chlorophyll- a matched the seasonal variability in the diversity of the anchovy prey and feeding intensity as reflected by the vacuity index, suggesting further investigation of the potential use of satellite-derived chlorophyll- a data as a proxy for anchovy feeding intensity.

  17. To What Degree Does Handling Concrete Molecular Models Promote the Ability to Translate and Coordinate between 2D and 3D Molecular Structure Representations? A Case Study with Algerian Students

    Science.gov (United States)

    Mohamed-Salah, Boukhechem; Alain, Dumon

    2016-01-01

    This study aims to assess whether the handling of concrete ball-and-stick molecular models promotes translation between diagrammatic representations and a concrete model (or vice versa) and the coordination of the different types of structural representations of a given molecular structure. Forty-one Algerian undergraduate students were requested…

  18. Structural characterization and rheological behavior of a heteroxylan extracted from Plantago notata Lagasca (Plantaginaceae) seeds.

    Science.gov (United States)

    Benaoun, Fatima; Delattre, Cédric; Boual, Zakaria; Ursu, Alina V; Vial, Christophe; Gardarin, Christine; Wadouachi, Anne; Le Cerf, Didier; Varacavoudin, Tony; Ould El-Hadj, Mohamed Didi; Michaud, Philippe; Pierre, Guillaume

    2017-11-01

    Plantago notata (Plantaginaceae) is a spontaneous plant from Septentrional Algerian Sahara currently used by traditional healers to treat stomach disorders, inflammations or wound healing. A water-soluble polysaccharide, called PSPN (PolySaccharide fraction from Plantago Notata), was extracted and purified from the seeds of this semi-arid plant. The structural features of this mucilage were evaluated by colorimetric assays, Fourier transformed infrared spectroscopy (FT-IR), gas chromatography coupled to mass spectrometry (GC/MS) and 1 H/ 13 C Nuclear Magnetic Resonance (NMR) spectroscopy. PSPN is a heteroxylan with a backbone composed of β-(1,3)-d-Xylp and β-(1,4)-d-Xylp highly branched, through (O)-2 and (O)-3 positions of β-(1,4)-d-Xylp by various side chains and terminal monosaccharides such as α-l-Araf-(1,3)-β-d-Xylp, β-d-Xylp-(1,2)-β-d-Xylp, terminal Xylp or terminal Araf. The physico-chemical and rheological analysis of this polysaccharide in dilute and semi diluted regimes showed that PSPN exhibites a molecular weight of 2.3×10 6 g/mol and a pseudoplastic behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. New insights on dust emission mechanisms in the central Sahara: observations from Fennec

    Science.gov (United States)

    Allen, Christopher; Washington, Richard

    2013-04-01

    The central Sahara is the dustiest region of the world in boreal summer. The Fennec project instrumented this remote region and the data that has come back has furnished some intriguing insights into the mechanisms of dust emission. Here, observations are presented for the June 2011 intensive observation period (IOP) from the supersite at Bordj-Badji Mokhtar (BBM), in south-west Algeria. Cold pool outflows produced 11 of the top 15 dustiest events at BBM. Their duration over BBM varied from 3-19h. Several of these outflows travelled long distances to reach the site (~600km). The average propagation speed of two of the dustiest, 11.6m/s and 16.2m/s, is much higher than the average speed of density currents in the Atlas foothills, estimated at 3-11.1m/s in published work by other authors. Such long-travelled currents also appear to have brought unexpectedly large dust particles to BBM: the three dust events during the IOP with the lowest Angstrom Exponent (≤0) are all convective outflows spawned by mesoscale convective complexes over western Niger. It is therefore possible that i) the sedimentology over the western Niger region provides much larger particles for emission than over the BBM region ii) the density currents over western Niger have much stronger gust fronts than those spawned near BBM, allowing much larger particles to be uplifted. A third possibility, which may have been the case on the night 16-17 June, is that dust was uplifted over Niger, transported in an elevated intrusion above a stable nocturnal surface layer, and then mixed down to the ground after the surface temperature inversion was eroded. 2m temperatures at BBM were between 1 and 2 standard deviations below the June mean on the morning of 17 June, making it possible that the 'cold pool' could in fact have been warmer than the surface and propagated as an elevated intrusion. Dry convective plume emission and low level jet (LLJ) induced emission and was also observed. Dry convective plume

  20. Sahara dust, ocean spray, volcanoes, biomass burning: pathways of nutrients into Andean rainforests

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    P. Fabian

    2009-10-01

    Full Text Available Regular rain and fogwater sampling in the Podocarpus National Park, on the humid eastern slopes of the Ecuadorian Andes, along an altitude profile between 1960 and 3180 m, has been carried out since 2002. The samples, accumulated over about 1-week intervals, were analysed for pH, conductivity and major ions (K+, Na+, NH4+, Ca2+, Mg2+, Cl, SO42−, NO3, PO43−.

    About 35% of the weekly samples had very low ion contents, with pH mostly above 5 and conductivity below 10 μS/cm. 10-days back trajectories (FLEXTRA showed that respective air masses originated in pristine continental areas, with little or no obvious pollution sources.

    About 65%, however, were significantly loaded with cations and anions, with pH as low as 3.5 to 4.0 and conductivity up to 50 μS/cm. The corresponding back trajectories clearly showed that air masses had passed over areas of intense biomass burning, active volcanoes, and the ocean, with episodic Sahara and/or Namib desert dust interference.

    Enhanced SO42− and NO3+ were identified, by combining satellite-based fire pixel observations with back trajectories, as predominantly resulting from biomass burning. Analyses of oxygen isotopes 16O, 17O, and 18O in nitrate show that nitrate in the samples is indeed a product of atmospheric conversion of precursors. Some SO42−, about 10% of the total input, could be identified to originate from active volcanoes, whose plumes were encountered by about 10% of all trajectories.

    Enhanced Na+, K+, and Cl were found to originate from ocean spray sources. They were associated with winds providing Atlantic air masses to the receptor site within less than 5 days. Episodes of

  1. Isotopic characteristic of meteoric water and groundwater in Ahaggar massif (central Sahara)

    International Nuclear Information System (INIS)

    Saighi, O.; Michelot, J.L.; Filly, A.

    2001-01-01

    The mean contents of both oxygen-18 and deuterium in precipitation from the Ahaggar massif (central Sahara) are: δ 18 O = -3 per mille and 2 H = -15 per mille. The heterogeneity in meteoric events and the great scattering of these isotopic contents can be ascribed to the origins and the histories of air masses. The main contribution comes from the inflow of the Guinean monsoon during summer months. During winter, the N/W winds, arriving in the area from the Moroccan coast, provide some rains. The deuterium excess of these precipitation are up to +10 per mille, indicating that the air masses generating these rains are supplied by the recycling of the continental air moisture. Groundwater resources are produced in some little phreatic aquifers, which are recharged by sporadic wadi floods. Aquifer zones that are the most favourable are located in the valleys and occur as three overlying levels of unequal importance: the alluvial aquifer, the weathered zone of the underlying substratum and the deep aquifer of fissured basement. The alluvial aquifer contain weakly mineralised water (0.3 g/l). Their stable isotopes contents (δ 18 O∼ -2.7 per mille) and 14 C activity of them (> 100 pmc) are comparable to present meteoric water, allowing modern meteoric waters to be identified. The weathered zone groundwater's are more mineralised (0.8 g/l) and its isotopic contents (δ 18 O∼ -4.2 per mille) and intermediate radiocarbon activity, prove their old water component. The basement's groundwater are more mineralised (> 1 g/l) and their very depleted isotopic contents (δ 18 O∼ -9 per mille) diverge clearly from the present precipitation. Furthermore, the absence of 3 H and 14 C activity of them, prove an old heritage, resulting from recharge during the last humid episode of the Holocene. (author)

  2. Actinopolyspora biskrensis sp. nov., a novel halophilic actinomycete isolated from Northern Sahara.

    Science.gov (United States)

    Saker, Rafika; Bouras, Noureddine; Meklat, Atika; Zitouni, Abdelghani; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

    2015-03-01

    A novel halophilic, filamentous actinomycete, designated H254(T), was isolated from a Saharan soil sample collected from Biskra (Northern Sahara), and subjected to a polyphasic taxonomic characterization. The strain is Gram-positive, aerobic, and halophilic, and the optimum NaCl concentration for growth is 15-20 % (w/v). The cell-wall hydrolysate contained meso-diaminopimelic acid, and the diagnostic whole-cell sugars were arabinose and galactose. The diagnostic phospholipid detected was phosphatidylcholine, and MK-9(H4) was the predominant menaquinone. The major fatty acid profiles were anteiso-C17:0 (32.8 %), C15:0 (28 %), and iso-C17:0 (12.3 %). Comparative analysis of the 16S rRNA gene sequences revealed that the strain H254(T) formed a well-separated sub-branch within the radiation of the genus Actinopolyspora, and the microorganism was most closely related to Actinopolyspora saharensis DSM 45459(T) (99.2 %), Actinopolyspora halophila DSM 43834(T) (99.1 %), and Actinopolyspora algeriensis DSM 45476(T) (99.0 %). Nevertheless, the strain had relatively lower mean values for DNA-DNA relatedness with the above strains (57.2, 68.4, and 45.6 %, respectively). Based on phenotypic features and phylogenetic position, we propose that strain H254(T) represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora biskrensis sp. nov. is proposed. The type strain of A. biskrensis is strain H254(T) (=DSM 46684(T) =CECT 8576(T)).

  3. Implications Of Fuelwood Demandon Sustainable Forest Conservation Of The Sub-Sahara Africa

    Directory of Open Access Journals (Sweden)

    Sogbon Odunwole

    2017-04-01

    Full Text Available Forests contribute immensely to economic and social development through formal trade in timber environmental services non- timber forest products safety net spiritual and aesthetic value. Wood is a key source of energy that has been used for millennia for cooking boiling water lighting and heating. Today about 2.5billion people depend on biomass energy for cooking and heating with 87 of this energy being provided by wood. In sub-Saharan African more than 90 of the population relies on wood fire that is firewood and charcoal as their primary source of domestic energy. Over 80 of urban householders and small industries use charcoal and firewood as their source of energy. Despite their numerous importance Africas forest continue to decline rapidly due to increase in agricultural practices into forest lands population growth and urbanization increased poverty high dependence on natural resources for subsistence and income through forest. The study centred on the implications of fuel wood demand on forest conservation in sub-Sahara Africa - a regional focus on Akure metropolitan area Ondo State. The specific objectives of the paper were to identify firewood consumption pattern in Akure metropolitan area and factors responsible for increased fuelwood demand in the study area. The paper adopted direct observation oral interview and 0.05 of the study area as sample size for the study. The study observed lack of adequate alternative poor implementation and enforcement of government regulation on forestry poverty and poor awareness on the menace of forest depletion among others. The paper posited provision of alternative fuel with subsidy regular awareness campaign proper monitoring implementation and enforcement of forest regulations with a view to achieving sustainable conservation.

  4. A new cichlid fish in the Sahara: The Ounianga Serir lakes (Chad), a biodiversity hotspot in the desert.

    Science.gov (United States)

    Trape, Sébastien

    In the rare perennial bodies of water of the Sahara desert, only a few fish species have survived to increasing aridification since the end of the last humid period at the Holocene, approximately 5000 years BP. Here, I report the occurrence of an undescribed haplochomine cichlid fish in Lake Boukou, one of the seven Ounianga Serir lakes (Chad). These lakes are located in one of the most arid areas of the Sahara desert, but they persist by virtue of subsurface inflow of fresh groundwater from a large fossil aquifer. Astatotilapia tchadensis sp. nov. is characterized by a black bar between eye and corner of mouth, rounded orange spots on anal fin, scales ctenoid, lower limb of first gill arch with 7-8 gill rackers, dorsal fin with 13-14 spines and 9-11 soft rays, anal fin with 3 spines and 8-9 soft rays, 29 or 30 lateral line scales, and lower pharyngeal dentition with enlarged molariform teeth. The new species is easily distinguished from A. desfontainii and A. flaviijosephii, the northernmost haplochromine species currently isolated from its other group members, and appears close to an unnamed species of Lake Chad basin. Ounianga Serir lakes and especially Lake Boukou present a remarkable diversity of fish, the highest known in the Sahara desert with a total of at least six fish species belonging to six genera and three families. They also constitute an exceptional natural landscape inscribed on the UNESCO world heritage list in 2012 and a biodiversity hotspot for desert vertebrate species. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  5. Role of Surface Wind and Vegetation Cover in Multi-decadal Variations of Dust Emission in the Sahara and Sahel

    Science.gov (United States)

    Kim, Dong; Chin, Mian; Remer, Lorraine A.; Diehl, Thomas L.; Bian, Huisheng; Yu, Hongbin; Brown, Molly E.; Stockwell, William R.

    2016-01-01

    North Africa, the world's largest dust source, is non-uniform, consisting of a permanently arid region (Sahara), a semi-arid region (Sahel), and a relatively moist vegetated region (Savanna), each with very different rainfall patterns and surface conditions. This study aims to better understand the controlling factors that determine the variation of dust emission in North Africa over a 27-year period from 1982 to 2008, using observational data and model simulations. The results show that the model-derived Saharan dust emission is only correlated with the 10-m winds (W10m) obtained from reanalysis data, but the model-derived Sahel dust emission is correlated with both W10m and the Normalized Difference Vegetation Index (NDVI) that is obtained from satellite. While the Saharan dust accounts for 82 of the continental North Africa dust emission (1340-1570 Tg year(exp -1) in the 27-year average, the Sahel accounts for 17 with a larger seasonal and inter-annual variation (230-380 Tg year(exp -1), contributing about a quarter of the transatlantic dust transported to the northern part of South America. The decreasing dust emission trend over the 27-year period is highly correlated with W10m over the Sahara (R equals 0.92). Over the Sahel, the dust emission is correlated with W10m (R 0.69) but is also anti-correlated with the trend of NDVI (R equals 0.65). W10m is decreasing over both the Sahara and the Sahel between 1982 and 2008, and the trends are correlated (R equals 0.53), suggesting that Saharan Sahelian surface winds are a coupled system, driving the inter-annual variation of dust emission.

  6. Saharo-Sindian buthid scorpions; description of two new genera and species from Occidental Sahara and Afghanistan

    Directory of Open Access Journals (Sweden)

    Wilson Lourenco

    2009-07-01

    Full Text Available Two new genera and species of Saharo-Sindian buthid scorpions are described on the basis of single specimens collected respectively in the deserts of Occidental Sahara and the North of Afghanistan. These new scorpion taxa represent further endemic relicts in the Saharo-Sindian faunas. Comments are also included on the evolution of the desert regions of North Africa and the Middle East, as well as the possible consequences of these events on the distribution of the extant scorpion fauna.

  7. Abdominal Obesity and their association with Total Body: Fat Distribution and Composition. Case of Algerian Teenager Male high school students

    Directory of Open Access Journals (Sweden)

    Mohammed Zerf

    2017-06-01

    Full Text Available Purpose: Our aim attempted to esteem the impact of abdominal fat on body fat distribution or composition related to total body fat as recommended weight loss among High School Students. Material: For the proposed, 100 male students from the Algerian high school Education Sector's mandate Sidi Bel Abbes, participate in the present study. Their average age 16±1.52 years, distributed into homogeneous groups, according to their body fat percent categories. Examined by saving tests (Body Fat Percentage (BFP - Abdominal circumference (WC - Body mass index (BMI. Results: Based on the test data and the analysis statistics applied, we confirm: a Abdominal obesity is excess body gain correlate with total fat BMI. It highly affected body composition reported as additional fat for overweight in compare with acceptable according to Ideal BFP categories. b Abdominal obesity is an amount deep fat correlates to total BFP. It higher influenced the distribution of total body fat reported as additional excess fat among overweight category compared to the acceptable group. c Waist circumference (WC is the leading marker of abdominal fat deposits located in the central region of the body. While the combination of body mass index (BMI and waist circumference (WC, reflects the combined effects of body build (fat or fatness in individuals at higher risk of excessive body fat. Conclusions: founded on the differences acquired by the research team. We highlight that abdominal obesity is strongly connected to larger WC relate to total body gain located as excess inordinate fatness BMI or fat distribution BFP among our overall sample. Evidence, which guides us to recommend our adolescent students to intensification their hours of sports practice, in order to avoid the consequences of abdominal obesity gain. Announced in the present study as excess abdominal adiposity more metabolically active. Requiring the control of body weight loss (BFP or BMI strongly correlates to

  8. Implications of high altitude desert dust transport from Western Sahara to Nile Delta during biomass burning season

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Anup K., E-mail: aprasad@chapman.ed [School of Earth and Environmental Sciences, Schmid College of Science, Chapman University, Orange, CA 92866 (United States); Center of Excellence in Earth Observing, Chapman University, Orange, CA 92866 (United States); El-Askary, Hesham [School of Earth and Environmental Sciences, Schmid College of Science, Chapman University, Orange, CA 92866 (United States); Center of Excellence in Earth Observing, Chapman University, Orange, CA 92866 (United States); Department of Environmental Sciences, Faculty of Science, Alexandria University, Moharem Bek, Alexandria 21522 (Egypt); National Authority for Remote Sensing and Space Science (NARSS), Cairo (Egypt); Kafatos, Menas [School of Earth and Environmental Sciences, Schmid College of Science, Chapman University, Orange, CA 92866 (United States); Center of Excellence in Earth Observing, Chapman University, Orange, CA 92866 (United States)

    2010-11-15

    The air over major cities and rural regions of the Nile Delta is highly polluted during autumn which is the biomass burning season, locally known as black cloud. Previous studies have attributed the increased pollution levels during the black cloud season to the biomass or open burning of agricultural waste, vehicular, industrial emissions, and secondary aerosols. However, new multi-sensor observations (column and vertical profiles) from satellites, dust transport models and associated meteorology present a different picture of the autumn pollution. Here we show, for the first time, the evidence of long range transport of dust at high altitude (2.5-6 km) from Western Sahara and its deposition over the Nile Delta region unlike current Models. The desert dust is found to be a major contributor to the local air quality which was previously considered to be due to pollution from biomass burning enhanced by the dominant northerly winds coming from Europe. - New evidence of desert dust transport from Western Sahara to Nile Delta during black cloud season and its significance for regional aerosols, dust models, and potential impact on the regional climate.

  9. Implications of high altitude desert dust transport from Western Sahara to Nile Delta during biomass burning season

    International Nuclear Information System (INIS)

    Prasad, Anup K.; El-Askary, Hesham; Kafatos, Menas

    2010-01-01

    The air over major cities and rural regions of the Nile Delta is highly polluted during autumn which is the biomass burning season, locally known as black cloud. Previous studies have attributed the increased pollution levels during the black cloud season to the biomass or open burning of agricultural waste, vehicular, industrial emissions, and secondary aerosols. However, new multi-sensor observations (column and vertical profiles) from satellites, dust transport models and associated meteorology present a different picture of the autumn pollution. Here we show, for the first time, the evidence of long range transport of dust at high altitude (2.5-6 km) from Western Sahara and its deposition over the Nile Delta region unlike current Models. The desert dust is found to be a major contributor to the local air quality which was previously considered to be due to pollution from biomass burning enhanced by the dominant northerly winds coming from Europe. - New evidence of desert dust transport from Western Sahara to Nile Delta during black cloud season and its significance for regional aerosols, dust models, and potential impact on the regional climate.

  10. The Role of Meteorology and Surface Condition to Multi-Decadal Variations of Dust Emission in Sahara and Sahel

    Science.gov (United States)

    Kim, D.; Chin, M.; Diehl, T. L.; Bian, H.; Brown, M. E.; Remer, L. A.; Stockwell, W. R.

    2014-12-01

    North Africa is the world's largest dust source region influencing regional and global climate, human health, and even the local economy. However North Africa as a dust source is not uniform but it consists of the arid region (Sahara) and the semi-arid region (Sahel) with emission rates depending on meteorological and surface conditions. Several recent studies have shown that dust from North Africa seems to have a decreasing trend in the past three decades. The goal of this study is to better understand the controlling factors that determine the change of dust in North Africa using observational data and model simulations. First we analyze surface bareness conditions determined from a long-term satellite observed Normalized Difference Vegetation Index for 1980-2008. Then we examine the key meteorological variables of precipitation and surface winds. Modeling experiments were conducted using the NASA Goddard Chemistry Aerosol Radiation and Transport (GOCART) model, which has been recently updated with a dynamic dust source function. Using the method we separate the dust originating from the Sahel from that of the Sahara desert. We find that the surface wind speed is the most dominant factor affecting Sahelian dust emission while vegetation has a modulating effect. We will show regional differences in meteorological variables, surface conditions, dust emission, and dust distribution and address the relationships among meteorology, surface conditions, and dust emission/loading in the past three decades (1980-2008).

  11. FeO-rich silicates in the Sahara 97159 (EH3) enstatite chondrite: Mineralogy, oxygen isotopic compositions, and origin

    Science.gov (United States)

    Kimura, M.; Hiyagon, H.; Lin, Y.; Weisberg, M. K.

    2003-03-01

    We report the mineralogy and oxygen isotopic compositions of FeO-rich silicates in the Sahara 97159 EH3 chondrite. This component is referred to as FeO-rich because it contains substantially more FeO than the characteristic FeO-poor silicates in the highly reduced enstatite meteorites. These FeO-rich silicates are mostly low-Ca pyroxene (Fs5­35) and their compositions suggest an origin under more oxidizing conditions, like those for the ordinary chondrites. However, the mafic silicates in ordinary and carbonaceous chondrites are dominantly olivine, and the FeO-rich silicates in the E chondrites are less commonly olivine. The oxygen isotopic compositions of the FeO- rich silicates are indistinguishable from those of FeO-poor silicates in Sahara 97159. These observations suggest that both the FeO-rich silicates and the FeO-poor silicates in EH chondrites formed from the same oxygen reservoir where redox conditions varied widely.

  12. Propolis-Sahara honeys preparation exhibits antibacterial and anti-biofilm activity against bacterial biofims formed on urinary catheters

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    Saad Aissat

    2016-11-01

    Full Text Available Objective: To evaluate the antibacterial effect of Sahara honeys (SHs against bacterial biofilms formed on urinary catheters in combination with propolis-Sahara honeys (P-SHs. Methods: Three clinical isolates were subjected to biofilm detection methods. The antibacterial and anti-biofilm activity for SHs and P-SHs were determined using agar well diffusion and the percentage of biofilm inhibition (PBI methods. Results: The PBI for Gram-positive bacteria [Staphylococcus aureus (S. aureus] was in the range of 0%–20%, while PBI for Gram-negative bacteria [Pseudomonas aeruginosa and Escherichia coli (E. coli] were in range of 17%–57% and 16%–65%, respectively. The highest PBI (65% was produced by SH2 only on E. coli. In agar well diffusion assay, zones of inhibition ranged from 11–20 mm (S. aureus, 9–19 mm (Pseudomonas aeruginosa and 11–19 mm (E. coli. The highest inhibition (20 mm was produced by SH1 only on S. aureus. In addition, the treatment of SHs and P-SHs catheters with a polymicrobial biofilms reduced biofilm formation after 48 h exposure period. Conclussions: SHs and P-SHs applied as a natural agent can be used as a prophylactic agent to prevent the formation of in vitro biofilm.

  13. Migration und Flucht aus Afrika südlich der Sahara - Historische Ursachen, aktuelle Auswirkungen, Lösungsansätze

    Science.gov (United States)

    Spaeth, Andreas

    2018-04-01

    Since decolonization till todays "New Odyssey" - the current European refugee crisis—(Kingsley 2016) we witnessed an unhindered and unrestricted migration to Europe from Africa south of the Sahara. Regulated migration was even promoted for medical staff, soldiers and seamen. This was induced by a shortage of qualified staff in receiving ex-colonial powers and the need maintaining mercenary armies for todays international conflicts. Political refugees were often hoped to form new western-friendly governments in cases of socialist Ethiopia and dictatorial regimes in esp. ex-Zaire, Togo, Guinea-Conakry, Uganda, Ghana and Zimbabwe. Todays migration out of Africa south of the Sahara is often caused by political and humanitarian crises, but specifically accelerated by the long-lasting negligence of donors for small-scale agricultural development. Land grabbing and the challenge to bring millions of youth with formal training into a meaningful occupation are seen as further important causes of rural outmigration. A "mismatch" between training programs offered especially by international development agencies and training needs for employability is also causing mass-unemployment of youth. An alignment of future development programming with the needs of the poor to assure a "right to stay" should be addressed by international policy makers with highest priority.

  14. Microphysical properties of Sahara dust collected during the Fennec campaign in 2011

    Science.gov (United States)

    Rocha Lima, Adriana; Vanderlei Martins, Jose; Todd, Martin; Washington, Richard; Marshan, John; Allen, Christopher; Engelstaedter, Sebastian; Cavazos-Guerra, Carolina

    2013-04-01

    Ground measurements of the atmospheric particles are extremely important in order to integrate aerial and remote sensing measurements. In situ aerosol filters collection and in situ measurements of aerosol properties were performed at two locations: Bordj Badj Mokthar in Algeria (Supersite 1) and Bir Moghrein in Mauritania (Supersite 2) in June 2011, as part of the Fennec project over the central Sahara. At Supersite 1 an automatized system consisting of an Aerosol Sampling Station (LASS1) and an integrated Reflectometer-Nephelometer allowed simultaneous collection of aerosol particles on Nuclepore filters (coarse and fine mode) and continuous measurement of the scattering and absorption properties of the aerosol particles. At the Supersite 2 in Mauritania a second Aerosol Sampling Station (LASS2) was also operational during the Fennec campaign collecting filters continually. Filters were sent back to laboratory for a series of analysis to obtain the optical and microphysical properties of the sampled aerosol particles. Gravimetric analysis of each individual filter gives the concentration of aerosol particles in μg-m3. Particle size distribution is obtained by scanning electron microscopy and the spectral reflectance of the filters from (350-2200nm) is being measured to derive the spectral mass absorption coefficient and refractive index of the aerosol particles. Preliminary analyses of Supersite 1 for 463nm, 525nm and 637nm wavelength show single scattering albedo 0.94, 0.96 and 0.98 respectively. X-Ray Fluorescence analyses of some of the filters from this location indicate Si, Fe, Al and Ca as the main constituent elements of these particles. At Supersite 2, it was observed periods of very clean conditions with concentrations below 10 μg-m3 (June 6-7, Maritime Phase) and periods of high dust concentration, with peaks of 70 μg-m3 (June 20-21, Heat Low Phase). Scanning electron microscopy analysis show high shape heterogeneity of particles and also the

  15. Integrated Health Care Systems and Indigenous Medicine: Reflections from the Sub-Sahara African Region

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    Beth Maina Ahlberg

    2017-09-01

    Full Text Available Indigenous or traditional medicine has, since the 1970s, been widely regarded as a resource likely to contribute to strengthening the health care systems in low income countries. This paper examines the state of traditional medicine using evidence from three case studies in Central Kenya. While the cases are too few to represent the broad diversity of cultures and related healing systems in the Sub-Sahara African Region, the way they seem to refute the main assumptions in the integration discourse is important, also because studies from other countries in the region report perspectives, similar to the case studies in Kenya. It is often argued that people continue to use traditional medicine because it is affordable, available, and culturally familiar. Its integration into the health care system would therefore promote cultural familiarity. The case studies however point to the loss of essential cultural elements central to traditional medicine in this particular area while users travel long distances to reach the healers. In addition, there are significant paradigm differences that may present obstacles to integration of the two systems. More problematic however is that integration is, as in many development interventions, a top-down policy that is rarely based on contextual realities and conditions. Instead, integration is often defined and dominated by biomedical professionals and health planners who may be unfamiliar or even hostile to some aspects of traditional medicine. Furthermore, integration efforts have tended to embrace selected components mostly herbal medicine. This has led to isolating herbal medicine from spiritualism, which may in turn affect the holistic perspective of traditional medicine. While familiarity and relevance may explain the continued use of traditional medicine, its services may not be as readily available, accessible, or even affordable as is often asserted. Globalization set in motion through colonization and

  16. Asociacionismo y cuestión nacional en el Sahara Occidental

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    Isaías Barreñada

    2012-12-01

    Full Text Available Desde mediados de la década pasada se ha operado una emergencia de la contestación política saharaui en los territorios ocupados por Marruecos. Este fenómeno se debe a varios factores entre los que cabe destacar los escasos resultados de las negociaciones políticas auspiciadas por Naciones Unidas, los cambios políticos operados en Marruecos, la frustración de la población saharaui ante la intensificación de la colonización y una creciente sensación de discriminación. Las protestas están en gran medida estructuradas por un tejido de asociaciones, la mayor parte de ellas alegales, que han hecho de la defensa de los derechos humanos su principal eje de actuación. Sus miembros son tanto antiguos militantes políticos como jóvenes que sólo han conocido la ocupación. El artículo aborda el proceso de articulación de estas asociaciones, sus actuaciones, sus nexos con Marruecos y con el resto de los saharauis, y presta especial atención a su carácter sustitutivo ante la imposibilidad de libre organización de los nacionalistas e independentistas. Since the middle of the last decade a growing political protest has emerged in Western Sahara occupied by Morocco. This phenomenon has been caused by several factors: the little results of the political negotiations under the United Nations, the political changes operated in Morocco, the frustration of the Sahrawi population facing the colonization and an increasing sensation of discrimination. To a great extent the protests are structured by associations, most of them non-legal, which have made of the defense of the human rights their main axis of performance. Most of their members are former political militants as young people who have only known the occupation. The article approaches the process of joining these associations, their performances, their ties with Morocco and the other Sahrawi, and gives special attention to its substitute character before the impossibility of free

  17. A reward for patience and suffering – Ethnomycology and commodification of desert truffles among Sahrawi refugees and nomads of Western Sahara

    NARCIS (Netherlands)

    Volpato, G.; Rossi, D.; Dentoni, D.

    2013-01-01

    A Reward for Patience and Suffering: Ethnomycology and Commodification of Desert Truffles among Sahrawi Refugees and Nomads of Western Sahara. This paper reflects on the role of ethnobiological knowledge and practices for refugees’ agency by focusing on the use and commodification of desert truffles

  18. Flight altitude of trans-Sahara migrants in autumn: a comparison of radar observations with predictions from meteorological conditions and water and energy balance models

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Biebach, H.

    2000-01-01

    Radar observations on the altitude of bird migration and altitudinal profiles of meteorological conditions over the Sahara desert are presented for the autumn migratory period. Migratory birds By at an average altitude of 1016 m (a.s.l.) during the day and 571 m during the night. Weather data served

  19. ARCHAEOLOGICAL AND ENVIRONMENTAL CHANGES BETWEEN 9500 BP AND 4500 BP: A CONTRIBUTION FROM THE SAHARA TO UNDERSTAND EXPANDING DROUGHTS IN THE “GREAT MEDITERRANEAN”

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    E. A.A. Garcea

    2013-03-01

    Full Text Available The Sahara is more connected to the Mediterranean than often assumed and palynology, in particular, has provided evidence of past interrelations between the Mediterranean and the Sahara with pollen spectra from prehistoric Saharan deposits including Mediterranean taxa. In order to show human-environment relationships and populations’ strategies in response to changing environments, this paper presents a case study from the southern Sahara. This region offered a natural laboratory for the study of human/climate interaction as the range of environmental change extended from flood to drought, forcing people to cope with periodic environmental instability. When the tropical rainfall belt migrated northward, watertable outcropped in interdunal depressions and formed permanent lakes, which alternated with severe arid spells. As a case study, this paper presents the results of interdisciplinary investigations on climate changes, human adaptations and subsistence strategies at Gobero, in the southern Sahara of Niger. Gobero is a restricted archaeological area comprising 8 sites that surround the shores of a palaeolake. It was intermittently occupied between about 9500 cal years BP and 4500 BP. Due to alternating environmental conditions it could only be occupied at the beginning and at the end of the most humid periods.

  20. Implementation of Information Communication Technology in the Teaching/Learning Process for Sustainable Development of Adults in West Africa Sub Sahara Region

    Science.gov (United States)

    Nwobi, Anthonia; Ngozi, Ugwuoke; Rufina, Nwachukwu; Ogbonnaya, Kingsley A.

    2016-01-01

    This study examines the implementation of information technology in the teaching/learning process for sustainable development of adults in West Africa Sub Sahara Region (WASSR). Three research questions and two hypotheses guided the study. The population for the study was 3071 participants and instructors drawn from 10 education centres that were…

  1. Transnational networks as a migration strategy. Algerians in the Ebro riverside / Redes transnacionales como estrategia migratoria. Argelinos en la ribera del Ebro

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    Anna Mata Romeu

    2015-10-01

    Full Text Available Networks can serve to cushion the weight they have on migrants living costs and disruption involved in immigration; determine, to some extent, who are those who migrate from communities and families; influence the selection of the places of destination and origin; maintaining links with society migrant origin and condition of the integration of migrants into the host society. Our premise is that networks exist and become important within the migration project, both in the way as in the settlement; but its use and intensity is extremely disparate and different, as we refer to one or another immigrant community. We delve into the ways in which they use in the group of Algerian origin settled in Spain, following field work developed in the Autonomous Community of Navarre (Spain between 2002 and 2013.

  2. A method for reducing model error while interpreting pressure derivative in well test analysis : application to Hassi Messaoud Algerian oil field

    Energy Technology Data Exchange (ETDEWEB)

    Bachar, S. [PED/AMT/Sonatrach Inc., Alger (Algeria); Deghmoum, A.H. [CRD/AMT/Sonatrach Inc., Alger (Algeria); Tiab, D. [Oklahoma Univ., Norman, OK (United States)

    2003-07-01

    A new method for reducing well test model error was presented. Improvements in exploiting the shape and the particular points of a pressure derivative curve have led to significant progress in reservoir characterization and development. The quality of measured pressure data can be affected by external or internal noise, resulting in amplified errors in computing pressure derivatives. The noise can also result in unreliable data of wellbore storage, flow regimes, reservoir permeability, and boundary limits. This newly developed model adjusts the derivative pressure in cases of vertical and horizontal wells, homogenous composite reservoirs, or naturally fractured reservoirs. It also includes buildup or drawdown tests. The numerical model is based on Tiab's Direct Synthesis method and is adapted to the Golub method. The paper presents case studies where the method has been applied to the Hassi Messaoud Algerian oil reservoir. 20 refs., 3 tabs., 8 figs.

  3. A humid corridor across the Sahara for the migration "Out of Africa" of early modern humans 120,000 years ago

    Science.gov (United States)

    Osborne, A. H.; Vance, D.; Rohling, E. J.; Barton, N.; Rogerson, M.; Fello, N.

    2008-12-01

    The climatic history of the Sahara in the Quaternary is likely to have been a key control on the history of human migrations out of Africa. For example, it is widely accepted that modern humans originated in sub- Saharan Africa around 150-200 thousand years ago (ka), but their route of dispersal across the currently hyper-arid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant around 120-90 ka, northward dispersal likely occurred during the humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130-117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of - now buried - fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. This would explain scattered findings at desert oases of Middle Stone Age (MSA) Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. We have previously used neodymium and oxygen isotope data to suggest that there was enhanced Nile outflow to the Levantine Sea during Saharan humid periods in Stage 5e and the Holocene1. Here, however, we present further geochemical data which suggest that the freshwater signal from Africa was much stronger further west in the Ionian Sea. Furthermore, analyses of shell samples retrieved from the Libyan fossil river channels traces the geochemical signature found in the Ionian Sea to the Tibesti Mountains in the southern Sahara. These data demonstrate that water in the fossil river systems of the Sahara derived from the south during wet episodes in general, and penetrated all the way to the Mediterranean during MIS 5e in particular, confirming the existence of an uninterrupted freshwater corridor across

  4. The predominance of codon 39 (c>t mutation of HBB gene in a portion of the Algerian population (Northeast Algeria

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    Belhadi Kamilia

    2017-04-01

    Full Text Available This study was planned to determine the frequency of β-thalassemia mutations in Batna region (Northeast Algeria. Nineteen blood samples of clinically thalassemic children patients were collected from Department of Pediatrics, University Hospital of Batna. We carried out the molecular genetics of beta globin gene by the method of minisequencing using Snapshot™ kit (Applied Biosystems in search of the four most common HBB genetic variants including three β-thalassemia mutations: codon 39(C>T (HBB: c.118C>T, IVSI-110(G>A (HBB: c.93-21G>A, and IVSI-1-2(T>G (HBB: c.92+2T>G, as well as the hemoglobin S variant (HBB: c.20A>T. We used direct DNA sequencing to detect the rare mutations of beta-globin gene. We have revealed the presence of four different β-globin gene mutations responsible for β-thalassemia in Batna region. According to our results, the nonsense mutation at codon 39 (C>T is the most frequent mutation type in our province, the same as other geographical regions of Algeria. It is followed by codon 54(-T, detected in a second Algerian family (the proband was homozygote, and the first association of Hb Knossos: codon 27 (G>T allele with codon 39 (C>T in the Algerian population. Here we reportws also the association of codon 39(C>T with IVS-I-110 (G>A. Our preliminary results show the predominance of codon 39 (c>t mutation of HBB gene in Batna region.

  5. Sahara 03505 sulfide-rich iron meteorite: Evidence for efficient segregation of sulfide-rich metallic melt during high-degree impact melting of an ordinary chondrite

    Science.gov (United States)

    Orazio, M. D.; Folco, L.; Chaussidon, M.; Rochette, P.

    2009-03-01

    The Sahara 03505 meteorite is a 65 g sulfide-rich iron found in an undisclosed locality of the Sahara. It consists of roughly equal volumetric proportion of polycrystalline troilite (crystal size 1.5-7.5 mm) enclosing cellular/dendritic metallic Fe-Ni (width of the dendrite arms, ~100 µm). The mineral assemblage is completed by sparse skeletal crystals of chromite, abundant droplets, 5- 100 µm in size, of anhydrous Fe-, Fe-Na-, and Fe-Mn-Mg-Ca-Na-K-phosphates, tiny crystals of schreibersite, and particles of metallic Cu. The medium- to fine-grained quench texture, and cooling modeling suggest that Sahara 03505 formed through crystallization of a sulfur-rich metallic melt under rapid cooling conditions (1- 4 °C s-1). The low troilite/metallic Fe-Ni ratio (~0.6 by weight) shows that this liquid was generated at much higher temperatures (>1300 °C) with respect to the FeS-Fe,Ni cotectic liquids. Based on bulk chemistry and oxygen isotope composition of chromite, we propose that Sahara 03505 formed by extensive impact melting of an ordinary chondrite lithology, followed by the efficient segregation of the immiscible silicate and metallic liquids. The sulfur-rich metallic liquid rapidly cooled either by radiation into space as a small lump, or by conduction to a chondrite country rock as a vein intruded into the walls of an impact crater. Sahara 03505 belongs to a small group of sulfide-rich iron meteorites which are characterized by medium- to fine-grained quench textures and by bulk chemistry that is different from the other iron meteorite groups. We propose here to use the descriptive term “sulfide-irons” for this meteorite group, by analogy with the stony-irons.

  6. Unusually abundant refractory inclusions from Sahara 97159 (EH3): a comparative study with other groups of chondrites

    Science.gov (United States)

    Lin, Y.; Kimura, M.; Hiyagon, H.; Monoi, A.

    2003-12-01

    Sixty-eight refractory inclusions and fragments were found in two polished thin sections of the Sahara 97159 EH3 chondrite, indicative of the highest abundance of refractory inclusions (22/cm 2, or 0.06 vol.%) in enstatite chondrites studied to date. All of the inclusions are intensely altered, mainly producing feldspathoids and albite, CaO depletion and minor Ti-rich compounds, such as Ti-sulfides. The alteration assemblages and FeO-poor spinel suggest that the reactions took place under reducing and SiO 2-rich conditions. This is consistent with the redox state of the host enstatite chondrite. The presence of Ti sulfides and low FeO alteration phases distinguishes alteration of E chondrite refractory inclusions from that of carbonaceous and ordinary chondrites. Most of the inclusions are referred to as Type A-like (35) and spinel-rich (26), respectively. Assuming melilite has been altered, these inclusions could be analogues of individual concentrically zoned objects of fluffy melilite-spinel-rich (Type A) and spinel-pyroxene-rich inclusions from carbonaceous chondrites such as the Ningqiang (CV anomalous) and Y 81020 (CO3) chondrites. Two inclusions consist mainly of Ca-pyroxene, fine-grained alteration products (feldspathoids and albite) and spinel. They are probably altered fragments of Ca-pyroxene-plagioclase-rich (Type C) inclusions, assuming all plagioclase has been altered to produce the fine-grained groundmass. Five other inclusions are hibonite and/or corundum bearing, similar to those reported in carbonaceous chondrites. Abundance ratios of various types of the inclusions from Sahara 97159 are similar to those from Ningqiang and Y 81020. Most of the observations, including mineral assemblages, mineral chemistry, texture, bulk compositions, O isotopic compositions and REE patterns, of the Sahara inclusions suggest a common reservoir of refractory inclusions in enstatite, ordinary and carbonaceous chondrites. The apparent differences, such as absence of

  7. Effect of Spanish style processing on the phenolic compounds and antioxidant activity of Algerian green table olives

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    Mettouchi, S.

    2016-03-01

    Full Text Available The study was carried out on seven Algerian olive cultivars to report the effect of Spanish style processing on individual and total phenolic compounds and the changes that occur in antioxidant capacity. The results indicate that the treatment leads to losses in phenolic contents which are cultivar dependent. Sigoise is the least affected variety (12.25% and Azzeradj from Seddouk the most affected one (94.80%. The phenolic profile shows drastic changes after processing. Hydroxytyrosol is dominant in processed olives (14.42–545.42 mg.100 g-1 while oleuropein is the major phenolic compound in fresh olives (994.27 mg.100 g-1. As a consequence to the loss in phenolic content, substantial reductions in the antioxidant activities of the extracts are noted. They are estimated to be 13.12–92.75% in scavenging activity against the DPPH radical, 37.78–93.98% in reducing capacity, 59.45–97.94% in the hydrogen peroxide radical and 7.26–51.66% in the inhibition bleaching of β-carotene. Among the processed varieties, only Sigoise presented a positive value of RACI (relative antioxidant capacity index.El estudio se llevó a cabo con siete variedades de aceitunas argelinas y se investigó el efecto de la elaboración al estilo español sobre los compuestos fenólicos individuales y totales; así como los cambios que se producen en la capacidad antioxidante. Los resultados obtenidos muestran que el procesamiento conduce a pérdidas en el contenido fenólico, lo cual es dependiente de la variedad. Sigoise es la variedad menos afectada (12.25% y Azzeradj de Seddouk la más (94.80%. El perfil fenólico muestra cambios drásticos después de su procesamiento. El hidroxitirosol es el polifenol predominante en aceitunas procesadas (14.42–545.42 mg·100 g−1, mientras que la oleuropeína es el compuesto fenólico mayoritario en las aceitunas frescas (994.27 mg·100 g−1. En consonancia con la pérdida en estos polifenoles, se detectaron reducciones

  8. South Asian Heart Risk Assessment (SAHARA): Randomized Controlled Trial Design and Pilot Study

    Science.gov (United States)

    Samaan, Zainab; Schulze, Karleen M; Middleton, Catherine; Irvine, Jane; Joseph, Phillip; Mente, Andrew; Shah, Baiju R; Pare, Guillaume; Desai, Dipika

    2013-01-01

    Background People of South Asian origin suffer a high burden of premature myocardial infarction (MI). South Asians form a growing proportion of the Canadian population and preventive strategies to mitigate the risk of MI in this group are needed. Prior studies have shown that multimedia interventions are effective and feasible in inducing health behavior changes among the obese, smokers, and among those who are sedentary. Objective Among at-risk South Asians living in Canada, our objectives are to determine: (1) the feasibility of a culturally tailored multimedia intervention to induce positive behavioral changes associated with reduced MI risk factors, and (2) the effectiveness and acceptability of information communicated by individualized MI and genetic risk score (GRS) reports. Methods The South Asian HeArt Risk Assessment (SAHARA) pilot study enrolled 367 individuals of South Asian origin recruited from places of worship and community centers in Ontario, Canada. MI risk factors including the 9p21 genetic variant status were provided to all participants after the baseline visit. Participants were randomly allocated to receive a multimedia intervention or control. The intervention group selected health goals and received personalized health messages to promote adherence to their selected goals. After 6 months, all participants had their MI risk factors repeated. The methods and results of this study are reported based on the CONSORT-EHEALTH guidelines. Results The mean age of participants was 53.8 years (SD 11.4), 52.0% (191/367) were women, and 97.5% (358/367) were immigrants to Canada. The mean INTERHEART risk score was 13.0 (SD 5.8) and 73.3% (269/367) had one or two copies of the risk allele for the 9p21 genetic variant. Both the intervention and control groups made some progress in health behavior changes related to diet and physical activity over 6 months. Participants reported that their risk score reports motivated behavioral changes, although half of

  9. Dust emission mechanisms in the central Sahara: new insights from remote field observations

    Science.gov (United States)

    Allen, C.; Washington, R.; Engelstaedter, S.

    2013-12-01

    North Africa is the world's largest source of mineral aerosol (dust). The Fennec Project, an international consortium led by the University of Oxford, is the first project to systematically instrument the remote central Sahara Desert. These observations have, among others, provided new insights into the atmospheric mechanisms of dust emission. Bordj Badji Mokhtar, in south-west Algeria, is within kilometres of the centre of the global mean summer dust maximum. The site, operated by Fennec partners ONM Algerie, has been heavily instrumented since summer 2011. During the Intensive Observation Period (IOP) in June 2011, four main emission mechanisms were observed and documented: cold pool outflows, low level jets (LLJs), monsoon surges and dry convective plumes. Establishing the relative importance of dust emission mechanisms has been a long-standing research goal. A detailed partitioning exercise of dust events during the IOP shows that 45% of the dust over BBM was generated by local emission in cold pool outflows, 14% by LLJs and only 2% by dry convective plumes. 27% of the dust was advected to the site rather than locally emitted and 12% of the dust was residual or ';background' dust. The work shows the primacy of cold pool outflows for dust emission in the region and also the important contribution of dust advection. In accordance with long-held ideas, the cube of wind speed is strongly correlated with dust emission. Surprisingly however, particles in long-range advection (>500km) were found to be larger than locally emitted dust. Although a clear LLJ wind structure is evident in the mean diurnal cycle during the IOP (12m/s peak winds at 935hPa between 04-05h), LLJs are only responsible for a relatively small amount of dust emission. There is significant daily variability in LLJ strength; the strongest winds are produced by a relatively small number of events. The position and strength of the Saharan Heat Low is strongly associated with the development (or

  10. The Sources of Moisture in the Sand Dunes – The Example of the Western Sahara Dune Field

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    Żmudzka Elwira

    2014-09-01

    Full Text Available Climatic and meteorological conditions may limit the aeolian transport within barchans. An explanation of that issue was the main goal of the investigation held in Western Sahara dune fields located around Tarfaya and Laâyoune. Particular attention was paid to the factors causing the moisture content rising of the sand dune surface layer, which could influence the wind threshold shear velocity in the aeolian transport. The wetted surface layer of sand, when receiving moisture from precipitation or suspensions, reduces the aeolian transport, even in case of wind velocity above 4-5 m s-1. Fog and dew condensation does not affect the moisture of deeper sand layers, what occurs after rainfall.

  11. Bensaâd Ali (dir., L’eau et ses enjeux au Sahara, Iremam, Karthala, 2011, 242 p.

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    Jean-Louis Marçot

    2011-11-01

    Full Text Available Je dirai en premier ma déception. Comme le suggère Ali Bensaâd à l’entrée du livre qu’il a dirigé, l’enjeu de l’eau au Sahara n’est ni plus ni moins que la conservation de la vie dans ce milieu qui lui est particulièrement hostile - la vie sous tous ses aspects. Or cet enjeu « vital » a été négligé au profit d’une approche micro-géographique. C’est pourtant par cette entrée que le travail collectif aurait pu légitimement intéresser un vaste public. Comment l’eau existe-t-elle à l’état naturel...

  12. On the geographic distribution of Scarabaeus (Scarabaeus aegyptiacus Stolfa, 1938 (Coleoptera: Scarabaeidae: first record from Atlantic Sahara (southwestern Morocco

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    J. L. Ruiz

    2017-03-01

    Full Text Available Scarabaeus aegyptiacus is a species widely distributed from the Arabian Peninsula to Morocco, occupying mainly arid and desert regions. Despite its wide geographic range, the number of known localities is very low (ten locations and its populations seem apparently fragmented and spaced. During a recent field survey in southwestern Morocco, we found a population of S. aegyptiacus in a rocky steppe (hamada near Msied (Tan-Tan province, Guelmin-Smara region, which constitutes the first record from Atlantic Sahara and extends about 1000 km to the southwest its known distribution. The specimens were found in a water cistern (“matfiya” in the local language, infrastructure that acts as a deadly trap for many animals, especially reptiles, amphibians and epigean arthropods, whose negative effect on invertebrate communities has not yet been evaluated. Chorological information of the species is synthesized and data on the habitat are provided.

  13. África al sur del Sahara: conflictos y degradación ambiental en el Sahel

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    Stella Maris Shmite

    2015-08-01

    Full Text Available The Sahel is a region located south of the Sahara Desert that is affected by a combination of problems, including droughts, soil degradation, demographic pressure, malnutrition, poverty, migration, conflicts, and refugees, among others. In this region, environmental changes strongly impact sociocultural, political and economic dimensions. These changes also act as multipliers of social tensions and stimulate political instability. The goal of this article is to identify these problems and analyze environmental variables to address the territorial context. This study seeks to interpret a range of sources, such as cartographical data, statistics and academic publications, that may allow for not only the complex network of persisting conflicts but also emerging conflicts in this cross-border African region to be comprehensively visualized and understood.

  14. Source apportionment and seasonal variation of PM2.5 in a Sub-Sahara African city: Nairobi, Kenya

    Science.gov (United States)

    Gaita, S. M.; Boman, J.; Gatari, M. J.; Pettersson, J. B. C.; Janhäll, S.

    2014-04-01

    Sources of airborne particulate matter and their seasonal variation in urban areas in Sub-Sahara Africa are poorly understood due to lack of long-term measurement data. In view of this, airborne fine particles matter (particle diameter ≤ 2.5 μm, PM2.5) were collected between May 2008 and April 2010 at two sites (urban background site and suburban site) within the Nairobi metropolitan area. A total of 780 samples were collected and analyzed for particulate mass, black carbon (BC) and thirteen trace elements. The average PM2.5 concentration at the urban background site was 20 ± 8 μg m-3 whereas the concentration at the suburban site was 13 ± 8 μg m-3. The daily PM2.5 concentrations exceeded 25 μg m-3 (the World Health Organization 24 h guideline value) 29% of the days at the urban background site and 7% of the days at the suburban site. At both sites, BC, Fe, S and Cl accounted for approximately 80% of all detected elements. Positive Matrix Factorization analysis identified five source factors that contribute to PM2.5 in Nairobi; traffic, mineral dust, secondary aerosol, industrial and combustion. Mineral dust and traffic factors were related to approximately 74% of PM2.5. Identified source factors exhibited seasonal variation though traffic factor was prominently consistent throughout the sampling period. The results provide information that can be exploited for policy formulation and mitigation strategies to control air pollution in Sub-Sahara African cities.

  15. Changing patterns of mobility as a response to climatic deterioration and aridification in the middle Holocene Southern Sahara.

    Science.gov (United States)

    Stojanowski, Christopher M; Knudson, Kelly J

    2014-05-01

    The African Humid Period witnessed a rapid human re-occupation of the Sahara as numerous lakes formed during the Holocene climatic optimum circa 10-5 kya. Permanent waters attracted a variety of aquatic and terrestrial fauna allowing for long-term occupation of specific paleolake basins. The Gobero paleolake in central Niger was one such location that preserves a unique mortuary record from the southern Sahara. Here, we use radiogenic strontium isotope analysis to investigate how human communities adapted to aridification throughout the Holocene. In particular, we examine the effects of increasing climate instability on patterns of human mobility. Results of radiogenic strontium isotope analysis of enamel and bone samples from Middle Holocene burials (∼7.2-4.9 kya) indicate predominantly local values with no evidence for sex-based variation. Comparisons of radiogenic strontium isotope data with previously published (Stojanowski and Knudson: Am J Phys Anthropol 146 (2011) 49-61) Early Holocene burials (∼9.7-8.3 kya) indicate significant differences in both enamel and bone values. Middle Holocene individuals demonstrate a predominantly non-local signature for enamel values and a predominantly local signature for bone values. Those individuals with non-local bone values always demonstrated non-local enamel values; however, the opposite was not the case. This suggests a divergence of mobility strategies during the Middle Holocene with a minority of individuals maintaining a more mobile existence throughout their life and others maintaining a similar strategy as Early Holocene hunter-gatherers that was tied to the paleolake basin. The more mobile individuals likely lived during the terminal phase of the lake's occupation. One response to aridification by Saharan peoples, then, was increasing mobility. Copyright © 2014 Wiley Periodicals, Inc.

  16. Normalized difference water indexes have dissimilar performances in detecting seasonal and permanent water in the Sahara-Sahel transition zone

    Science.gov (United States)

    Campos, João C.; Sillero, Neftalí; Brito, José C.

    2012-09-01

    SummaryThe decrease of water resources can enhance poverty and increase insecurity in dry regions, at the same time leading to loss of biological diversity. For these reasons, the information about surface perennial and well-known water sources in the arid and semi-arid regions of Africa has been mapped. However, seasonal water can be missed in mapping due to their short and erratic appearance, while the mapping of any aquatic resources represents a foremost priority for protecting social, economic and biological values in the e.g. Sahara-Sahel transition zone. Therefore, Remote Sensing becomes crucial to monitor a variety of wetland systems in these regions. This work evaluates the performance of three Normalized Difference Water Indexes [Gao's NDWI (NDWINIR/MIR), McFeeters' NDWI (NDWIG/NIR) and Xu's NDWI (NDWIG/MIR)] in mapping of water systems across Mauritania. Maps with seasonal and permanent water were derived, using a multi-temporal series of Landsat 5 TM and Landsat 7 ETM+ images. The performance of indexes was compared based on 551 control points collected during five fieldwork missions to Mauritania between 2007 and 2011. Control points were separated in three classes of water availability (permanent, seasonal and non-water points) and then randomly assigned into two data sets: one for selecting the water availability thresholds for index reclassification and another for threshold validation. NDWIG/MIR and NDWINIR/MIR had good performances in detecting permanent and seasonal water, respectively, while NDWIG/NIR failed to detect most of the water bodies. The threshold selection generated water maps with seasonal and permanent features that might be missing in simple mapping of aquatic systems. The extensive data collection provides novel information about NDWI performances for water delineation in arid and semi-arid regions and for a future management of aquatic environments of the Sahara-Sahel transition zone.

  17. Algerian hydrocarbon magnet

    International Nuclear Information System (INIS)

    Jackson, K.

    1996-01-01

    Algeria is the world's seventh largest gas producer and currently boasts one of the biggest gas fields - Hassi R'Mel -discovered to date. Recording the highest number of oil and gas discoveries anywhere in the world in 1994, the country is proving to be a magnet for foreign oil companies despite its continued political instability and the security risks posed by Islamic fundamentalists. Some 40,000 lives have been lost since Islamic militants began fighting the government in 1992, including a number of foreign journalists and two foreign pipeline workers. (author)

  18. Glider and satellite high resolution monitoring of a mesoscale eddy in the Algerian basin: effects on the mixed layer depth and biochemistry

    Science.gov (United States)

    Cotroneo, Yuri; Aulicino, Giuseppe; Ruiz, Simón; Pascual, Ananda; Budillon, Giorgio; Fusco, Giannetta; Tintoré, Joaquin

    2016-04-01

    Despite of the extensive bibliography about the circulation of the Mediterranean Sea and its sub-basins, the debate on mesoscale dynamics and its impacts on biochemical processes is still open because of their intrinsic time scales and of the difficulties in sampling. In order to clarify some of these processes, the "Algerian BAsin Circulation Unmanned Survey - ABACUS" project was proposed and realized through access to JERICO Trans National Access (TNA) infrastructures between September and December 2014. In this framework, a deep glider cruise was carried out in the area between Balearic Islands and Algerian coasts to establish an endurance line for monitoring the basin circulation. During the mission, a mesoscale eddy, identified on satellite altimetry maps, was sampled at high-spatial horizontal resolution (4 km) along its main axes and from surface to 1000 m depth. Data were collected by a Slocum glider equipped with a pumped CTD and biochemical sensors that collected about 100 complete casts inside the eddy. In order to describe the structure of the eddy, in situ data were merged with new generation remotely sensed data as daily synoptic sea surface temperature (SST) and chlorophyll concentration (Chl-a) images from MODIS satellites as well as sea surface height and geostrophic velocities from AVISO. From its origin along the Algerian coast in the eastern part of the basin, the eddy propagated to north-west at a mean speed of about 4 km/day with a mean diameter of 112/130 km, a mean elevation of 15.7 cm and clearly distinguished by the surrounding waters thanks to its higher SST and Chl-a values. Temperature and salinity values along the water column confirm the origin of the eddy from the AC showing the presence of recent Atlantic water in the surface layer and Levantine Intermediate Water (LIW) in the deeper layer. Eddy footprint is clearly evident in the multiparametric vertical sections conducted along its main axes. Deepening of temperature, salinity and

  19. A study of the relict fish fauna of northern Chad, with the first records of a polypterid and a poeciliid in the Sahara desert.

    Science.gov (United States)

    Trape, Sébastien

    2013-01-01

    Seventeen species and sub-species of fishes belonging to four families (Cyprinidae, Clariidae, Aplocheilidae, Cichlidae) were known to occur in perennial bodies of water in the Sahara desert. The study of fishes collected in Lake Boukou near Ounianga Serir (Borkou, northern Chad) shows, for the first time, the occurrence in the Sahara desert of relict populations of Polypterus senegalus (Polypteridae) and Poropanchax normani (Poeciliidae). The Cichlidae Tilapia zilli was also collected in this lake. With these new records, the relict fish fauna currently known in lakes and gueltas of the Borkou plateaus comprises six species. In the Ennedi Mountains, where the specific status of Barbus populations was unclear, B. macrops was collected in Bachikere guelta. The toad Amietophrynus regularis was collected in Ounianga Kebir. Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  20. Démocratisation en Afrique au sud du Sahara (1989-1992) : un aperçu de la littérature

    NARCIS (Netherlands)

    Buijtenhuijs, R.; Rijnierse, E.; Foreign Affairs language services, Amsterdam

    1993-01-01

    Ce rapport présente un aperçu de la littérature sur la démocratisation en Afrique au sud du Sahara (1989-1992). D'abord, les auteurs évoquent un certain nombre de traits dominants de la vie politique en Afrique qui forment l'arrière-plan nécessaire à comprendre les changements actuels concernant la

  1. REE and actinide microdistribution in Sahara 97072 and ALHA77295 EH3 chondrites: A combined cosmochemical and petrologic investigation

    Science.gov (United States)

    Gannoun, A.; Boyet, M.; El Goresy, A.; Devouard, B.

    2011-06-01

    We report the results of rare earth elements (REEs) and U-Th inventory of individual minerals (oldhamite, enstatite and niningerite) in two of the most unequilibrated and primitive EH3 known so far, ALHA77295 and Sahara 97072. Under the highly reducing condition that prevailed during the formation of enstatite chondrites, REEs are mainly chalcophile and concentrated in oldhamite. The study is guided by detailed petrographic investigations of the individual minerals in chondrules, complex sulfide-metal clasts and enstatite-dominated matrices. We developed two textural parameters in order to resolve the evolution of oldhamite condensates and their residence in the solar gas prior to their accretion in the individual objects or in matrices and relate these textural features to the measured REE patterns of the individual oldhamite crystals. These textural parameters are the crystal habit of oldhamite grains (idiomorphic or anhedral) and their host assemblages. REE concentrations were measured by SIMS and LA-ICPMS. Oldhamite grains display REE enrichments (10-100 × CI). Four types of REE patterns are encountered in oldhamite in ALHA77295. In general the REE distributions cannot be assigned to a specific oldhamite-bearing assemblage. The most represented REE pattern is characterized by both slight to large positive Eu and Yb anomalies and is enriched in light REEs relative to heavy REEs. This pattern is present in 97% of oldhamite in Sahara 97072, suggesting a different source region in the reduced part of the nebula or different parental EH asteroids for the two EH3 chondrites. Different parental asteroids are also supported by MgS-FeS zoning profiles in niningerite grains adjacent to troilite revealing both normal and reverse zoning trends and different MnS contents. The observed homogeneity of REE distribution in oldhamite grains in Sahara 97072 is not related to the mild metamorphic event identified in this meteorite that caused breakdown of the major K- and Rb

  2. Algerian mint species: high performance thin layer chromatography quantitative determination of rosmarinic acid and in vitro inhibitory effects on linoleic acid peroxidation

    Directory of Open Access Journals (Sweden)

    Brahmi Fatiha

    2014-12-01

    Full Text Available Objective: To determine the quantitative paremeters of rosmarinic acid in Algerian mints, Mentha spicata L. (M. spicata, Mentha pulegium L. and Mentha rotundifolia (L. Huds by high performance thin layer chromatography (HPTLC-densitometric method and screen the effects of these plant extracts on linoleic acid peroxidation. Methods: The analyses were performed on HPTLC silica gel 60 F254 plates with chloroform: acetone: formic acid (75:16.5:8.5, v/v as the mobile phase. Rosmarinic acid was determined in UV at 365 nm and fluorescence at λexc 325 nm with a 550 nm filter, respectively. The effects of plants extracts on linoleic acid peroxidation were measured by an indirect in vitro colorimetric method. Results: Chromatographic resolution permitted reliable quantification in both measurement modes and calibration curves were linear in a range of 150-1 000 ng/spot. M. spicata was found to contain significantly higher concentrations of rosmarinic acid. The densitometric quantification allowed the analysis of many samples in a short time with reasonable precision (total precision for Mentha spp extracts, 5.1% and 5.8% for UV and fluorescence detection, respectively. The HPTLC data, allied to assays of linoleic acid peroxidation prevention, suggested the potential of M. spicata (52% Trolox® equivalents as a natural source for inhibitors of lipid peroxidation. Conclusions: Densitometry can be used for routine determination and quality control of rosmarinic acid in herbal and formulations containing Mentha species.

  3. Association of MTHFR C677T and A1298C gene polymorphisms with methotrexate efficiency and toxicity in Algerian rheumatoid arthritis patients

    Directory of Open Access Journals (Sweden)

    Lilya M. Berkani

    2017-11-01

    Full Text Available Methotrexate (MTX is the most used drug in rheumatoid arthritis (RA treatment. However, it shows variability in clinical response, which is explained by an association with genetic polymorphisms. This study aimed to elucidate the role of the two gene polymorphism C677T and A1298C of the methylenetetrahydrofolate reductase (MTHFR in response to MTX in Algerian RA patients. Study included 54 early RA patient treated with MTX for one year. MTX efficiency and toxicity were evaluated at 6 and 12 months respectively and the two gene polymorphisms were genotyped. No association was found between A1298C polymorphism and MTX toxicity. However, T allele of the C677T polymorphism was associated with the occurrence of MTX adverse effects (p = 0,019, OR: 3,63, 95% CI [1,12 - 12,80]. No association was found between C677T polymorphism and MTX efficiency, while A allele of the A1298C polymorphism was associated with good and moderate response (p = 0,02, OR = 3,28, 95% CI: [1,11– 9,42]. The study of RA biological markers kinetics showed that MTX did not affect antibodies rate unlike inflammatory markers. Our study suggests that MTHFR C677T and A1298C genotyping are associated to MTX toxicity and efficiency, respectively, in RA patients. This offers new perspectives in the personalization of RA treatment in Algeria. Keywords: Genetics, Clinical genetics, Internal medicine, Health sciences

  4. In vitro antibacterial activities of aqueous extracts from Algerian desert truffles (Terfezia and Tirmania, Ascomycetes) against Pseudomonas aeruginosa and Staphylococcus aureus.

    Science.gov (United States)

    Gouzi, Hicham; Belyagoubi, Larbi; Abdelali, Khadidja Nesrine; Khelifi, Adila

    2011-01-01

    The aim of this study is to evaluate the in vitro effects of aqueous extracts of three species of Algerian desert truffles (Terfezia claveryi, T. leonis, and Tirmania nivea) on the growth of Pseudomonas aeruginosa and Staphylococcus aureus. The antimicrobial activity of the three aqueous extracts was tested using the agar well diffusion and kinetic bacterial growth curves methods. The aqueous extracts of Terfezia claveryi and Tirmania nivea were found to possess a very powerful antibacterial activity against both S. aureus and P. aeruginosa using agar well diffusion. Using 4% and 11% of the aqueous extracts of T. claveryi and T. nivea in the growth medium of S. aureus caused a significant inhibition of S. aureus growth by 86.48% and 99.09%, respectively. The aqueous extracts of T. claveryi and T. nivea were found to cause a significant inhibition of the growth of P. aeruginosa by 71.11% and 100%, respectively. However, the aqueous extract of Terfecia leonis did not show any antibacterial activity. Therefore, T. claveryi and Tirmania nivea can be considered a source of natural therapeutic agents that can be used to treat eye infections caused by resistant bacteria such as P. aeruginosa and S. aureus.

  5. Yeasts isolated from Algerian infants's feces revealed a burden of Candida albicans species, non-albicans Candida species and Saccharomyces cerevisiae.

    Science.gov (United States)

    Seddik, Hamza Ait; Ceugniez, Alexandre; Bendali, Farida; Cudennec, Benoit; Drider, Djamel

    2016-01-01

    This study aimed at showing the yeast diversity in feces of Algerian infants, aged between 1 and 24 months, hospitalized at Bejaia hospital (northeast side of the country). Thus, 20 colonies with yeast characteristics were isolated and identified using biochemical (ID32C Api system) and molecular (sequencing of ITS1-5.8S-ITS2 region) methods. Almost all colonies isolated (19 strains) were identified as Candida spp., with predominance of Candida albicans species, and one strain was identified as Saccharomyces cerevisiae. Screening of strains with inhibitory activities unveiled the potential of Candida parapsilosis P48L1 and Candida albicans P51L1 to inhibit the growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. Further studies performed with these two Candida strains revealed their susceptibility to clinically used antifungal compounds and were then characterized for their cytotoxicity and hemolytic properties. On the other hand, Saccharomyces cerevisiae P9L1 isolated as well in this study was shown to be devoid of antagonism but resulted safe and overall usable as probiotic.

  6. Seasonal assessment of biological indices, bioaccumulation and bioavailability of heavy metals in mussels Mytilus galloprovincialis from Algerian west coast, applied to environmental monitoring

    Directory of Open Access Journals (Sweden)

    Omar Rouane-Hacene

    2015-10-01

    Full Text Available The aim of the present work is to broaden our knowledge on the variability of trace metals in mussel tissues, focusing on seasonal fluctuations in the three different sampling sites of Algerian west coast (Oran Harbor (S1, Ain Defla (S2 and Hadjaj (S3. For this purpose, the bioavailability (metal indices and bioaccumulation (metal concentrations in soft tissues of heavy metals (Zn, Cu, Pb, and Cd, and the physiological characteristics (e.g. biological indices such as condition index (CI of mussels Mytilus galloprovincialis have been assessed and related to seasons and sites. In S1, the highest levels of metal concentrations and indices were obtained in mussels sampled in winter for Zn, Cu and Cd, but in summer for Pb. The biological indices significantly decreased in winter. In S2, the levels of concentrations and indices of all metals varied whatever the seasons, excepting in summer where the values were the lowest. In summer and spring, the biological indices were lower than in autumn and winter. The low growth of organisms in spring and summer might be correlated to the reproductive period and the low trophic level known in S2. S3, considered as a “pristine” area, showed low metal concentrations and indices, and high biological indices, reflecting the favorable physiological conditions for the mussel growth. This approach might be used in the monitoring of the quality of coastal waters and the present work provided a useful data set for Mediterranean monitoring network.

  7. [Preliminary evaluation of the antioxidant trace elements in an Algerian patient with type 2 diabetes: special role of manganese and chromium].

    Science.gov (United States)

    Harani, Hassiba; Otmane, Amel; Makrelouf, Mohamed; Ouadahi, Nacer; Abdi, Arezki; Berrah, Abdelkrim; Zenati, Akila; Alamir, Barkahoum; Koceir, Elhadj Ahmed

    2012-01-01

    In type 2 diabetes, the relationship between antioxidants and insuline-like trace elements is very complex during oxidative stress, being mediated by hyperglycemia, dyslipidemia and inflammation. We investigated the antioxidant status, particularly Mn and Cr on the diabetes metabolic control, and their interaction with the metabolic syndrome (MS) parameters. The study was undertaken on 278 Algerian diabetic subjects who were divided in 2 groups according to glycated hemoglobin (HbA(1c)) 7% value, attesting for a good or poor metabolic control of diabetes, respectively. The MS was defined according to NCEP-ATPIII. Insulin resistance was evaluated by HOMA-IR model. The plasma manganese concentrations was significantly increased in both diabetics groups, independently of metabolic control. However, chromium (Cr) seems to play a determinant action in metabolic control, as shown by better values of insulin resistance (HOMA-IR) and HbA(1c). The selenium status was positively correlated with glutathion peroxidase activity. Copper and zinc plasma levels in the diabetic patients were similar to those of control subjects. In conclusion, our results suggest that Mn play a crucial role in antioxidant capacity and we hypothesize that antioxidant defense is preserved in the cytosol (superoxide dismutase Cu/Zn -SOD), whereas it is impaired in mitochondria (Mn-SOD), which makes this cell organelle a true therapeutic target in diabetes.

  8. THE EFFECT OF SOXHLET AND ULTRASONIC-ASSISTED EXTRACTION ON ANTIOXIDANT COMPONENTS AND ANTIOXIDANT PROPERTIES OF SELECTED SOUTH ALGERIAN RED POTATOES CULTIVARS

    Directory of Open Access Journals (Sweden)

    TOUHAMI LANEZ

    2017-12-01

    Full Text Available The present work aimed to study the effect of two different commonly applied extraction techniques for the evaluation of total phenolic contents (TPC, total flavonoid contents (TFC and total antioxidant capacity (TAC of fresh south Algerian red potatoes cultivars (Solanum tuberosum L. These techniques are namely Soxhlet extraction (SE and ultrasonic-assisted extraction combines with maceration (UAE-M for 5 min, 2 hours and 24 hours. A 40 kHz probe was used for the sonication at 3 different amplitudes (30 %, 50 %, and 70 % with a mixture of ethanol/water at ratios of 70:30 and 100 % v/v as solvent. TPC and TFC obtained using SE are respectively 13.94 mg gallic acid equivalents (GAE / g extract and 11.32 mg rutin equivalents (RE / g extract, the amount of these contents is increased to 22.29 mg GAE / g extract and 85.93 mg RE / g extract using UAE-M with 100 % ethanol at amplitude 30 % and 24 hours maceration time. HPLC analysis of samples extract shows four contents with different concentration. In addition, all the results demonstrate a statistically significant with (p < 0.001. It should be noted that the use of UAE-M proved to be faster and more efficient process when compared to Soxhlet extraction.

  9. Identification and quantification of furanocoumarins in stem bark and wood of eight Algerian varieties of Ficus carica by RP-HPLC-DAD and RP-HPLC-DAD-MS.

    Science.gov (United States)

    Rouaiguia-Bouakkaz, Samia; Amira-Guebailia, Habiba; Rivière, Céline; Delaunay, Jean-Claude; Waffo-Téguo, Pierre; Mérillon, Jean-Michel

    2013-04-01

    Furanocoumarins are the major phytoalexins of Ficus carica and are effective natural drug candidates for treatment of several types of cancer and skin disease. The objectives of this study were to analyze and quantify linear furanocoumarins, mainly psoralen and bergapten, in wood and bark of stems from eight Algerian varieties of fig and to establish the differences in the content of these metabolites in the eight local samples. Psoralen and bergapten contents in the stem bark and wood (in microg/g DW) varied respectively from 146.6 to 1110.3 and from 395.7 to 1671.8 for psoralen, and from 114.3 to 524.0 and from 144.2 to 718.6 for bergapten. This study fills a gap in our knowledge of furanocoumarin distribution in different parts of the fig tree. Psoralen and bergapten concentrations were higher in the wood than in the stem bark. Most of the dark fruited fig trees produce these two coumarins more than the green ones.

  10. Green Synthesis of Cationic Polyacrylamide Composite Catalyzed by An Ecologically Catalyst Clay Called Maghnite-H+ (Algerian MMT Under Microwave Irradiation.

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    Rahmouni Abdelkader

    2016-08-01

    Full Text Available In this study, a novel green cationic hydrogel of cationic polyacrylamide composite have been prepared and investigated. The synthesis of green cationic polyacrylamide composite was evaluated for its solubility in water. The reactions were performed using acrylamide monomer, solvent, catalyst (clay fin called maghnite and solution of  H2SO4 (0.25 M, with the system under microwave irradiation (160 ºC for 4 min. Major factors affecting the polymerization reaction were studied with a view to discover appropriate conditions for preparation of the composite. The cationic polyacrylamide obtained is the subject of future studies of modification and transformation. The resulting polymer has been characterized by a variety of characterization techniques, such as: Fourier Transform Infrared Spectra and 1H NMR spectra.  Copyright © 2016 BCREC GROUP. All rights reserved Received: 10th June 2015; Revised: 2nd September 2015; Accepted: 5th January 2016 How to Cite: Abdelkader, R., Mohammed, B. (2016. Green Synthesis of Cationic Polyacrylamide Composite Catalyzed by An Ecologically  Catalyst Clay Called Maghnite-H+ (Algerian MMT Under Microwave Irradiation. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (2: 170-175 (doi:10.9767/bcrec.11.2.543.170-175 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.2.543.170-175

  11. Solving Bi-Objective Optimal Power Flow using Hybrid method of Biogeography-Based Optimization and Differential Evolution Algorithm: A case study of the Algerian Electrical Network

    Directory of Open Access Journals (Sweden)

    Ouafa Herbadji

    2016-03-01

    Full Text Available This paper proposes a new hybrid metaheuristique algorithm based on the hybridization of Biogeography-based optimization with the Differential Evolution for solving the optimal power flow problem with emission control. The biogeography-based optimization (BBO algorithm is strongly influenced by equilibrium theory of island biogeography, mainly through two steps: Migration and Mutation. Differential Evolution (DE is one of the best Evolutionary Algorithms for global optimization. The hybridization of these two methods is used to overcome traps of local optimal solutions and problems of time consumption. The objective of this paper is to minimize the total fuel cost of generation, total emission, total real power loss and also maintain an acceptable system performance in terms of limits on generator real power, bus voltages and power flow of transmission lines. In the present work, BBO/DE has been applied to solve the optimal power flow problems on IEEE 30-bus test system and the Algerian electrical network 114 bus. The results obtained from this method show better performances compared with DE, BBO and other well known metaheuristique and evolutionary optimization methods.

  12. What Happened in the Sahara? A Transition over the Bound of Semi-consciousness in Paul Bowles’ The Sheltering Sky

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    Sina Movaghati

    2017-03-01

    Full Text Available Paul Bowles’ prodigious novel, The Sheltering Sky, is an epitome of a narrative about the Modern Man and his existentialistic dilemmas. After six decades from its initial publication, The Sheltering Sky, still, attracts multitudinous attention for its esoteric and abstruse nature of the occurrences. In regard to nomadic-diasporic lifestyle of the author, and his protagonists, normally, many critical approaches to the text have shifted toward hyper-textual perusals. By mentioning the noteworthy scholarly works which have been done hitherto, this article tries to be faithful to the text as much as possible, and elucidates the myth that, what has really happened in the Sahara which coerced the protagonists to forget their identities to this great extent; thus, hectic and deranged, divagating in the desert, inclining toward the destruction of their identities. In this article, in regard to textual substantiations, ‘Sand’ and ‘Time’ are adduced as the two crucial elements which balance two main protagonists’ state of semi-consciousness, in the inside journey of self. Also, the concept of ‘humanistic identity,’ from Bowles’ viewpoint, in connexion to the setting of the novel, will be discussed.

  13. Viruses in the desert: a metagenomic survey of viral communities in four perennial ponds of the Mauritanian Sahara.

    Science.gov (United States)

    Fancello, Laura; Trape, Sébatien; Robert, Catherine; Boyer, Mickaël; Popgeorgiev, Nikolay; Raoult, Didier; Desnues, Christelle

    2013-02-01

    Here, we present the first metagenomic study of viral communities from four perennial ponds (gueltas) located in the central Sahara (Mauritania). Three of the four gueltas (Ilij, Molomhar and Hamdoun) are located at the source of three different wadis belonging to the same hydrologic basin, whereas the fourth (El Berbera) belongs to a different basin. Overall, sequences belonging to tailed bacteriophages were the most abundant in all four metagenomes although electron microscopy and sequencing confirmed the presence of other viral groups, such as large DNA viruses. We observed a decrease in the local viral biodiversity in El Berbera, a guelta with sustained human activities, compared with the pristine Ilij and Molomhar, and sequences related to viruses infecting crop pests were also detected as a probable consequence of the agricultural use of the soil. However, the structure of the El Berbera viral community shared the common global characteristics of the pristine gueltas, that is, it was dominated by Myoviridae and, more particularly, by virulent phages infecting photosynthetic cyanobacteria, such as Prochlorococcus and Synechococcus spp. In contrast, the Hamdoun viral community was characterized by a larger proportion of phages with the potential for a temperate lifestyle and by dominant species related to phages infecting heterotrophic bacteria commonly found in terrestrial environments. We hypothesized that the differences observed in the structural and functional composition of the Hamdoun viral community resulted from the critically low water level experienced by the guelta.

  14. Intercomparison of Satellite Dust Retrieval Products over the West African Sahara During the Fennec Campaign in June 2011

    Science.gov (United States)

    Banks, J.R.; Brindley, H. E.; Flamant, C.; Garay, M. J.; Hsu, N. C.; Kalashnikova, O. V.; Klueser, L.; Sayer, A. M.

    2013-01-01

    Dust retrievals over the Sahara Desert during June 2011 from the IASI, MISR, MODIS, and SEVIRI satellite instruments are compared against each other in order to understand the strengths and weaknesses of each retrieval approach. Particular attention is paid to the effects of meteorological conditions, land surface properties, and the magnitude of the dust loading. The period of study corresponds to the time of the first Fennec intensive measurement campaign, which provides new ground-based and aircraft measurements of the dust characteristics and loading. Validation using ground-based AERONET sunphotometer data indicate that of the satellite instruments, SEVIRI is most able to retrieve dust during optically thick dust events, whereas IASI and MODIS perform better at low dust loadings. This may significantly affect observations of dust emission and the mean dust climatology. MISR and MODIS are least sensitive to variations in meteorological conditions, while SEVIRI tends to overestimate the aerosol optical depth (AOD) under moist conditions (with a bias against AERONET of 0.31), especially at low dust loadings where the AODproperties on the retrievals is also investigated. Over elevated surfaces IASI retrieves AODs which are most consistent with AERONET observations, while the AODs retrieved by MODIS tend to be biased low. In contrast, over the least emissive surfaces IASI significantly underestimates the AOD (with a bias of -0.41), while MISR and SEVIRI show closest agreement.

  15. África al sur del Sahara: conflictos y degradación ambiental en el Sahel

    Directory of Open Access Journals (Sweden)

    Stella Maris Shmite

    2015-01-01

    Full Text Available El Sahel es una región ubicada al sur del desierto del Sahara, donde se conjugan múltiples problemáticas: sequías, degradación de suelos, presión demográfica, desnutrición, pobreza, migraciones, conflictos, refugiados, entre otras. Los cambios ambientales provocan un fuerte impacto en las dimensiones socioculturales, políticas y económicas, actúan como multiplicadores de las tensiones sociales y estimulan la inestabilidad política. El objetivo de este artículo es identificar estas problemáticas y analizar las variables ambientales, con el fin de abordar el contexto territorial. La investigación se orientó hacia la interpretación de diversas fuentes como cartografía, estadísticas y publicaciones académicas, que abren la posibilidad de mirar y comprender de manera integral la compleja trama de conflictos que perduran, así como los emergentes en este territorio transfronterizo de África.

  16. Origin of kamacite, schreibersite, and perryite in metal-sulfide nodules of the enstatite chondrite Sahara 97072 (EH3)

    Science.gov (United States)

    Lehner, Stephen W.; Buseck, Peter R.; McDonough, William F.

    2010-02-01

    Perryite [(Fe,Ni)x(Si,P)y], schreibersite [(Fe,Ni)3P], and kamacite (αFeNi) are constituent minerals of the metal-sulfide nodules in the Sahara 97072 (EH3) enstatite chondrite meteorite. We have measured concentrations of Ni, Cu, Ga, Au, Ir, Ru, and Pd in these minerals with laser ablation, inductively coupled plasma mass spectrometry (ICP-MS). We also measured their Fe, Ni, P, Si, and Co concentrations with electron microprobe. In kamacite, ratios of Ru/Ir, Pd/Ir, and Pd/Ru cluster around their respective CI values and all elements analyzed plot near the intersection of the equilibrium condensation trajectory versus Ni and the respective CI ratios. In schreibersite, the Pd/Ru ratio is near the CI value and perryite contains significant Cu, Ga, and Pd. We propose that schreibersite and perryite formed separately near the condensation temperatures of P and Si in a reduced gas and were incorporated into Fe-Ni alloy. Upon further cooling, sulfidation of Fe in kamacite resulted in the formation of additional perryite at the sulfide interface. Still later, transient heating re-melted this perryite near the Fe-FeS eutectic temperature during partial melting of the metal-sulfide nodules. The metal-sulfide nodules are pre-accretionary objects that retain CI ratios of most siderophile elements, although they have experienced transient heating events.

  17. Impacts of the Sahel-Sahara Interface Reforestation on West African Climate: Intraseasonal Variability and Extreme Precipitation Events

    Directory of Open Access Journals (Sweden)

    Ibrahima Diba

    2016-01-01

    Full Text Available This study aims to evaluate the impacts of the Sahel-Sahara interface reforestation on spatiotemporal variability of the summer rainfall and extreme precipitation events over West Africa using the RegCM4 model. The land surface scheme of RegCM4 was modified to incorporate an East-West reforested zone (15°N and 20°N. Two runs were performed using the standard version of RegCM4 and the modified one of the same model taking into account the incorporated forest. The reforestation significantly modifies rainfall signal over West Africa by increasing it over the reforested zone and the Fouta Jallon highlands (FJH. This rainfall increase is associated with a strengthening of the atmospheric moisture over the reforested area. This atmospheric moisture content increase associated with the wind dynamic may explain the spatiotemporal change of the rainfall and extreme precipitation events. The analysis of the impacts of the reforestation on some rainfall indices shows an increase of the 90th, 95th, and 99th percentiles over the reforested zone and off the FJH. This reforestation also causes an increase of the maximum length of the consecutive wet days over and off FJH and a decrease of the maximum length of the consecutive dry days over the northern Sahel and the reforested zone.

  18. Laser Desorption/Ionization-Time of Flight (LDI-TOF and Matrix-Assisted Laser Desorption/Ionization - Time of Flight (MALDI – TOF mass spectrometry of an Algerian asphaltene

    Directory of Open Access Journals (Sweden)

    T. Fergoug

    2017-09-01

    Full Text Available Both LDI-TOF and MALDI-TOF Mass spectroscopy experiments of an Algerian asphaltene derived from a deposit were performed. LDI mass experiments were conducted for both linear and reflectron modes under laser wavelength/attenuation variation. The different LDI-Mass spectra show that mass distribution depends on experimental condition for masses below 1000 amu and that the average molecular weight is around 650 for the polar fraction and beyond 1000 amu for non-polar ones. The use of different matrices as CHCA, HABA and Dithranol changes slightly the aspect of the spectra.

  19. Extraction et composition chimique d'huile de noyaux de dattes algériennes [Extraction and chemical composition of algerian date seeds oil

    Directory of Open Access Journals (Sweden)

    Zahida BOUSSENA

    2016-12-01

    Full Text Available Introduction. The date palm ( fruit was composed by fleshy pericarp and seeds. The average weight of date pits (seeds ranges from 13% and 15% of weight of date. The date seeds are rich in some minerals, especially iron, total sugars and crude fat. Objective. The chemical composition of Algerian date seeds oils was determined after extraction. Materials and methods. Four varieties of date seeds and their mixture, composed by 50% Deglet nour, 20% Degla baida, 20% Mech degla and 10% Hamraya, were investigated. Oil extraction was carried out by soxhlet with petrol ether 40-60°C. The oils were converted to methyl esters by the method of ISO 5508-1990. The fatty acid methyl esters were analyzed by gas chromatography Results. Oil contents in date seeds represented 6.20%-10.39% and in the mixture 11.67%. Gas chromatography revealed that the major unsaturated fatty acid (UFA was oleic acid (36.17%- 41.61% in date seeds of four varieties, and 35.50% in the mixture. The main saturated fatty acid (SFA was lauric acid, with average values of 7.14%-23.59%, and that of the mixture was 29.37%. The average values of myristic, palmitic and linoleic acids were ranged between 6.65% to 15.99% and those of the mixture was 5.53%. Low values of stearic, capric and caprylic acids were noted (2.24% and 3.64%, 0.13% and 0.48%, 0.10% and 0.44%, respectively, and that of the mixture was 58.95%. Total SFA represented 23.32%-40.58% and that of the mixture was 58.95%, and total UFA were 57.60%-73.03% and that of the mixture was 41.04%. Conclusion A potential use of date seeds oil can be considered in food, cosmetics, and pharmaceutics applications.

  20. Diversity of Microbial Communities in Production and Injection Waters of Algerian Oilfields Revealed by 16S rRNA Gene Amplicon 454 Pyrosequencing

    Science.gov (United States)

    Lenchi, Nesrine; İnceoğlu, Özgül; Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Llirós, Marc; Servais, Pierre; García-Armisen, Tamara

    2013-01-01

    The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three different types of samples were analyzed: production waters from flooded wells, production waters from non-flooded wells and injection waters used for flooding (water-bearing formations). Microbial communities of production and injection waters appeared to be significantly different. From a quantitative point of view, injection waters harbored roughly ten times more microbial cells than production waters. Bacteria dominated in injection waters, while Archaea dominated in production waters. Statistical analysis based on the relative abundance and bacterial community composition (BCC) revealed significant differences between production and injection waters at both OTUs0.03 and phylum level. However, no significant difference was found between production waters from flooded and non-flooded wells, suggesting that most of the microorganisms introduced by the injection waters were unable to survive in the production waters. Furthermore, a Venn diagram generated to compare the BCC of production and injection waters of one flooded well revealed only 4% of shared bacterial OTUs. Phylogenetic analysis of bacterial sequences indicated that Alpha-, Beta- and Gammaproteobacteria were the main classes in most of the water samples. Archaeal sequences were only obtained from production wells and each well had a unique archaeal community composition, mainly belonging to Methanobacteria, Methanomicrobia, Thermoprotei and Halobacteria classes. Many of the bacterial genera retrieved had already

  1. Diversity of Microbial Communities in Production and Injection Waters of Algerian Oilfields Revealed by 16S rRNA Gene Amplicon 454 Pyrosequencing.

    Directory of Open Access Journals (Sweden)

    Nesrine Lenchi

    Full Text Available The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three different types of samples were analyzed: production waters from flooded wells, production waters from non-flooded wells and injection waters used for flooding (water-bearing formations. Microbial communities of production and injection waters appeared to be significantly different. From a quantitative point of view, injection waters harbored roughly ten times more microbial cells than production waters. Bacteria dominated in injection waters, while Archaea dominated in production waters. Statistical analysis based on the relative abundance and bacterial community composition (BCC revealed significant differences between production and injection waters at both OTUs0.03 and phylum level. However, no significant difference was found between production waters from flooded and non-flooded wells, suggesting that most of the microorganisms introduced by the injection waters were unable to survive in the production waters. Furthermore, a Venn diagram generated to compare the BCC of production and injection waters of one flooded well revealed only 4% of shared bacterial OTUs. Phylogenetic analysis of bacterial sequences indicated that Alpha-, Beta- and Gammaproteobacteria were the main classes in most of the water samples. Archaeal sequences were only obtained from production wells and each well had a unique archaeal community composition, mainly belonging to Methanobacteria, Methanomicrobia, Thermoprotei and Halobacteria classes. Many of the bacterial genera

  2. New Method for Nucleophilic Substitution on Hexachlorocyclotriphosphazene by Allylamine Using an Algerian Proton Exchanged Montmorillonite Clay (Maghnite-H+ as a Green Solid Catalyst

    Directory of Open Access Journals (Sweden)

    Lahouaria Medjdoub

    2016-08-01

    Full Text Available Nucleophilic substitution on hexachlorocyclotriphosphazene (HCCTP with allylamine in order to give hexa(allylaminocyclotriphosphazene (HACTP  is performed for the first time under mild conditions by using diethylether as solvent to replace benzene which is very toxic. The reaction time is reduced to half and also performed at room temperature but especially in the presence of an eco-catalyst called Maghnite-H+. This catalyst has a significant role in the industrial scale. In fact, the use of Maghnite is preferred for its many advantages: a very low purchase price compared to other catalysts, the easy removal of the reaction mixture. Then, Maghnite-H+ is became an excellent catalyst for many chemical reactions. The structure of HACTP synthesized in the presence of Maghnite-H+ to 5% by weight is confirmed by 1H-NMR, 13C-NMR, 31P-NMR (Nuclear magnetic resonance and FTIR (Fourier Transform Infrared spectroscopy. MALDI-TOF (Matrix-Assisted Laser Desorption/Ionisation-time-of-flight mass spectrometry is used to establish the molecular weight of HACTP which is 471 g/mol. DSC (Differential Scanning Calorimetery and TGA (Thermogravimetric Analysis show that HACTP is a crystalline product with a melting point of 88 °C. It is reactive after melting but is degraded from 230 °C. Copyright © 2016 BCREC GROUP. All rights reserved Received: 28th September 2015; Revised: 5th December 2015; Accepted: 4th January 2016 How to Cite: Medjdoub, L., Mohammed, B. (2016. New Method for Nucleophilic Substitution on Hexachlorocyclotriphosphazene by Allylamine Using an Algerian Proton Exchanged Montmorillonite Clay (Maghnite-H+ as a Green Solid Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (2: 151-160 (doi:10.9767/bcrec.11.2.541.151-160 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.2.541.151-160

  3. Crocodiles in the Sahara Desert: An Update of Distribution, Habitats and Population Status for Conservation Planning in Mauritania

    Science.gov (United States)

    Brito, José C.; Martínez-Freiría, Fernando; Sierra, Pablo; Sillero, Neftalí; Tarroso, Pedro

    2011-01-01

    Background Relict populations of Crocodylus niloticus persist in Chad, Egypt and Mauritania. Although crocodiles were widespread throughout the Sahara until the early 20th century, increased aridity combined with human persecution led to local extinction. Knowledge on distribution, occupied habitats, population size and prey availability is scarce in most populations. This study evaluates the status of Saharan crocodiles and provides new data for Mauritania to assist conservation planning. Methodology/Principal Findings A series of surveys in Mauritania detected crocodile presence in 78 localities dispersed across 10 river basins and most tended to be isolated within river basins. Permanent gueltas and seasonal tâmoûrts were the most common occupied habitats. Crocodile encounters ranged from one to more than 20 individuals, but in most localities less than five crocodiles were observed. Larger numbers were observed after the rainy season and during night sampling. Crocodiles were found dead in between water points along dry river-beds suggesting the occurrence of dispersal. Conclusion/Significance Research priorities in Chad and Egypt should focus on quantifying population size and pressures exerted on habitats. The present study increased in by 35% the number of known crocodile localities in Mauritania. Gueltas are crucial for the persistence of mountain populations. Oscillations in water availability throughout the year and the small dimensions of gueltas affect biological traits, including activity and body size. Studies are needed to understand adaptation traits of desert populations. Molecular analyses are needed to quantify genetic variability, population sub-structuring and effective population size, and detect the occurrence of gene flow. Monitoring is needed to detect demographical and genetical trends in completely isolated populations. Crocodiles are apparently vulnerable during dispersal events. Awareness campaigns focusing on the vulnerability and

  4. The effect of a dynamic background albedo scheme on Sahel/Sahara precipitation during the mid-Holocene

    Directory of Open Access Journals (Sweden)

    F. S. E. Vamborg

    2011-02-01

    Full Text Available We have implemented a new albedo scheme that takes the dynamic behaviour of the surface below the canopy into account, into the land-surface scheme of the MPI-ESM. The standard (static scheme calculates the seasonal canopy albedo as a function of leaf area index, whereas the background albedo is a gridbox constant derived from satellite measurements. The new (dynamic scheme additionally models the background albedo as a slowly changing function of organic matter in the ground and of litter and standing dead biomass covering the ground. We use the two schemes to investigate the interactions between vegetation, albedo and precipitation in the Sahel/Sahara for two time-slices: pre-industrial and mid-Holocene. The dynamic scheme represents the seasonal cycle of albedo and the correspondence between annual mean albedo and vegetation cover in a more consistent way than the static scheme. It thus gives a better estimate of albedo change between the two time periods. With the introduction of the dynamic scheme, precipitation is increased by 30 mm yr−1 for the pre-industrial simulation and by about 80 mm yr−1 for the mid-Holocene simulation. The present-day dry bias in the Sahel of standard ECHAM5 is thus reduced and the sensitivity of precipitation to mid-Holocene external forcing is increased by around one third. The locations of mid-Holocene lakes, as estimated from reconstructions, lie south of the modelled desert border in both mid-Holocene simulations. The magnitude of simulated rainfall in this area is too low to fully sustain lakes, however it is captured better with the dynamic scheme. The dynamic scheme leads to increased vegetation variability in the remaining desert region, indicating a higher frequency of green spells, thus reaching a better agreement with the vegetation distribution as derived from pollen records.

  5. Crocodiles in the Sahara desert: an update of distribution, habitats and population status for conservation planning in Mauritania.

    Science.gov (United States)

    Brito, José C; Martínez-Freiría, Fernando; Sierra, Pablo; Sillero, Neftalí; Tarroso, Pedro

    2011-02-25

    Relict populations of Crocodylus niloticus persist in Chad, Egypt and Mauritania. Although crocodiles were widespread throughout the Sahara until the early 20(th) century, increased aridity combined with human persecution led to local extinction. Knowledge on distribution, occupied habitats, population size and prey availability is scarce in most populations. This study evaluates the status of Saharan crocodiles and provides new data for Mauritania to assist conservation planning. A series of surveys in Mauritania detected crocodile presence in 78 localities dispersed across 10 river basins and most tended to be isolated within river basins. Permanent gueltas and seasonal tâmoûrts were the most common occupied habitats. Crocodile encounters ranged from one to more than 20 individuals, but in most localities less than five crocodiles were observed. Larger numbers were observed after the rainy season and during night sampling. Crocodiles were found dead in between water points along dry river-beds suggesting the occurrence of dispersal. Research priorities in Chad and Egypt should focus on quantifying population size and pressures exerted on habitats. The present study increased in by 35% the number of known crocodile localities in Mauritania. Gueltas are crucial for the persistence of mountain populations. Oscillations in water availability throughout the year and the small dimensions of gueltas affect biological traits, including activity and body size. Studies are needed to understand adaptation traits of desert populations. Molecular analyses are needed to quantify genetic variability, population sub-structuring and effective population size, and detect the occurrence of gene flow. Monitoring is needed to detect demographical and genetical trends in completely isolated populations. Crocodiles are apparently vulnerable during dispersal events. Awareness campaigns focusing on the vulnerability and relict value of crocodiles should be implemented. Classification

  6. Crocodiles in the Sahara desert: an update of distribution, habitats and population status for conservation planning in Mauritania.

    Directory of Open Access Journals (Sweden)

    José C Brito

    Full Text Available BACKGROUND: Relict populations of Crocodylus niloticus persist in Chad, Egypt and Mauritania. Although crocodiles were widespread throughout the Sahara until the early 20(th century, increased aridity combined with human persecution led to local extinction. Knowledge on distribution, occupied habitats, population size and prey availability is scarce in most populations. This study evaluates the status of Saharan crocodiles and provides new data for Mauritania to assist conservation planning. METHODOLOGY/PRINCIPAL FINDINGS: A series of surveys in Mauritania detected crocodile presence in 78 localities dispersed across 10 river basins and most tended to be isolated within river basins. Permanent gueltas and seasonal tâmoûrts were the most common occupied habitats. Crocodile encounters ranged from one to more than 20 individuals, but in most localities less than five crocodiles were observed. Larger numbers were observed after the rainy season and during night sampling. Crocodiles were found dead in between water points along dry river-beds suggesting the occurrence of dispersal. CONCLUSION/SIGNIFICANCE: Research priorities in Chad and Egypt should focus on quantifying population size and pressures exerted on habitats. The present study increased in by 35% the number of known crocodile localities in Mauritania. Gueltas are crucial for the persistence of mountain populations. Oscillations in water availability throughout the year and the small dimensions of gueltas affect biological traits, including activity and body size. Studies are needed to understand adaptation traits of desert populations. Molecular analyses are needed to quantify genetic variability, population sub-structuring and effective population size, and detect the occurrence of gene flow. Monitoring is needed to detect demographical and genetical trends in completely isolated populations. Crocodiles are apparently vulnerable during dispersal events. Awareness campaigns focusing on

  7. Internal diversification of non-Sub-Saharan haplogroups in Sahelian populations and the spread of pastoralism beyond the Sahara.

    Science.gov (United States)

    Kulichová, Iva; Fernandes, Verónica; Deme, Alioune; Nováčková, Jana; Stenzl, Vlastimil; Novelletto, Andrea; Pereira, Luísa; Černý, Viktor

    2017-10-01

    Today, African pastoralists are found mainly in the Sahel/Savannah belt spanning 6,000 km from west to east, flanked by the Sahara to the north and tropical rainforests to the south. The most significant group among them are the Fulani who not only keep cattle breeds of possible West Eurasian ancestry, but form themselves a gene pool containing some paternally and maternally-transmitted West Eurasian haplogroups. We generated complete sequences for 33 mitogenomes belonging to haplogroups H1 and U5 (23 and 10, respectively), and genotyped 16 STRs in 65 Y chromosomes belonging to haplogroup R1b-V88. We show that age estimates of the maternal lineage H1cb1, occurring almost exclusively in the Fulani, point to the time when the first cattle herders settled the Sahel/Savannah belt. Similar age estimates were obtained for paternal lineage R1b-V88, which occurs today in the Fulani but also in other, mostly pastoral populations. Maternal clade U5b1b1b, reported earlier in the Berbers, shows a shallower age, suggesting another possibly independent input into the Sahelian pastoralist gene pool. Despite the fact that animal domestication originated in the Near East ∼ 10 ka, and that it was from there that animals such as sheep, goats as well as cattle were introduced into Northeast Africa soon thereafter, contemporary cattle keepers in the Sahel/Savannah belt show uniparental genetic affinities that suggest the possibility of an ancient contact with an additional ancestral population of western Mediterranean ancestry. © 2017 Wiley Periodicals, Inc.

  8. 20th-Century Climate Change over Africa: Seasonal Variation in Hydroclimate Trends and Sahara Desert Extent

    Science.gov (United States)

    Nigam, S.; Thomas, N. P.

    2017-12-01

    Twentieth-century trends in seasonal temperature and precipitation over the African continent are analyzed from observational data sets and historical climate simulations. Given the agricultural economy of the continent, a seasonal perspective is adopted as it is more pertinent than an annual-average one which can mask off-setting but agriculturally-sensitive seasonal hydroclimate variations. Examination of linear trends in seasonal surface air temperature (SAT) shows that heat stress has increased in several regions, including Sudan and Northern Africa where largest SAT trends occur in the warm season. Broadly speaking, the northern continent has warmed more than the southern one in all seasons. Precipitation trends are varied but notable declining trends are found in the countries along the Gulf of Guinea, especially in the source region of Niger river in West Africa, and in the Congo river basin. Rainfall over the African Great Lakes - one of the largest freshwater repositories - has however increased. We show that the Sahara Desert has expanded significantly over the 20th century - by 12-20% depending on the season. The desert expanded southward in summer, reflecting retreat of the northern edge of the Sahel rainfall belt; and to the north in winter, indicating potential impact of the widening of the Tropics. Specific mechanisms driving the expansion in each season are investigated. Finally, this observational analysis is used to evaluate the state-of-the-art climate models from a comparison of the 20th-century hydroclimate trends with those manifest in historical climate simulations. The evaluation shows that modeling regional hydroclimate change over the Africa continent remains challenging.

  9. Le Sahara face à son miroir : poétiques du « point mort »

    OpenAIRE

    Bargados, Alberto López

    2015-01-01

    La question de la souveraineté du Sahara occidental est dans une impasse politique, avec les deux parties principales bloquées, chacune de son côté, sur des positions qui paraissent inamovibles, dans un contexte international qui, de facto, semble considérer comme acceptable le statu quo imposé par l’occupation marocaine de 1975-1976 et sanctionné par l’armistice de 1991. Cette situation de paralysie politique a entraîné un véritable blocage dans la représentation que la société espagnole se ...

  10. 26Al-26Mg systematics in D’Orbigny and Sahara 99555 angrites: Implications for high-resolution chronology using extinct chronometers

    Science.gov (United States)

    Spivak-Birndorf, Lev; Wadhwa, Meenakshi; Janney, Philip

    2009-09-01

    We report on an investigation of the 26Al- 26Mg isotope systematics in the D'Orbigny and Sahara 99555 angrites. High precision Mg isotope compositions and Al/Mg ratios were measured in mineral separates and whole rock samples from D'Orbigny and Sahara 99555 using multiple-collector inductively coupled plasma mass spectrometry (MC-ICPMS). Plagioclase separates from both angrites have resolvable excesses in 26Mg ( Δ26Mg) that correlate with their respective Al/Mg ratios. 26Al- 26Mg systematics in the mineral separates and whole rocks define precise isochrons that correspond to 26Al/ 27Al ratios of (5.06 ± 0.92) × 10 -7 and (5.13 ± 1.90) × 10 -7 and initial Δ26Mg values of -0.006 ± 0.040‰ and -0.016 ± 0.047‰ for D'Orbigny and Sahara 99555, respectively. The slopes and initial Δ26Mg values are identical for these two meteorites within errors and the data for both angrites considered together define an isochron corresponding to a 26Al/ 27Al ratio of (5.10 ± 0.55) × 10 -7 and initial Δ26Mg value of -0.012 ± 0.019. Relative to the Efremovka E60 CAI, the 26Al/ 27Al values reported here for these angrites imply 26Al- 26Mg ages of 4562.42 ± 0.29 Ma and 4562.43 ± 0.53 Ma for D'Orbigny and Sahara 99555, respectively. These 26Al- 26Mg ages are concordant with model ages determined using other extinct radionuclide chronometers (e.g., 53Mn- 53Cr and 182Hf- 182W), but are ˜2 Myr younger than the absolute 207Pb- 206Pb ages that have been reported recently for these angrites. The reason for this discrepancy is not presently known, but may imply disturbance of one or more of the isotope systems under consideration or a possible bias in the 207Pb- 206Pb ages of the angrites resulting from natural or analytical causes.

  11. Bistand for utvikling. Effekten av handelsrelatert bistand på økonomisk utvikling i land sør for Sahara

    OpenAIRE

    Bjerke, Marielle Veneranda

    2015-01-01

    Hensikten med denne oppgaven er å undersøke effekten av handelsrelatert bistand på økonomisk utvikling. Problemstillingen er som følger: Har den direkte effekten av handelsrelatert bistand en positiv effekt på økonomisk utvikling i land sør for Sahara, eller er effekten betinget av institusjonell kvalitet? Resultatene fra analysen ga signifikante resultater på den direkte effekten av handelsrelatert bistand på økonomisk utvikling. Det er ingen signifikante resultater i forholdet mellom de be...

  12. Study methods for borings carried out near the underground nuclear experiments in the Sahara. Part 2. techniques for studying the walls of the bore-holes

    International Nuclear Information System (INIS)

    Faure, J.

    1969-01-01

    Measurements by drilling have been carried out during the underground nuclear bomb explosions on the Sahara test site: observation of the rock by television and permeability measurements. After a presentation of the principle of the experiment, a description is given of the technique used, i.l. the equipment and its manipulation. Finally problems arising from the interpretation of the results are considered. The conclusion stresses the importance of the results of this work from the point of view of possible industrial applications. (author) [fr

  13. Occurence of ArmA and RmtB aminoglycoside resistance 16S rRNA methylases in extended-spectrum β-lactamases producing Escherichia coli in Algerian hospitals.

    Directory of Open Access Journals (Sweden)

    Amel Ayad

    2016-09-01

    Full Text Available The aim of this study was to characterize the extended-spectrum-β-lactamases (ESBLs producing clinical strains of Escherichia coli isolated between January 2009 and June 2012 from Algerian hospitals and to determine the prevalence of 16S rRNA methylase among them. Sixty-seven ESBL-producers were detected among the 239 isolates included: 52 CTX-M-15-producers, 5 CTX-M-3-producers, 5 CTX-M-1-producers, 2 CTX-M-14-producers, 2 SHV-12-producers and one TEM-167-producer. Among the ESBL-producing strains twelve harboured 16S rRNA methylase genes: 8 rmtB and 4 armA. rmtB was located on a IncFIA plasmid and armA was located either on a IncL/M or a IncFIA plasmid. RmtB-producing isolates were genotypically related and belonged to the sequence type ST 405 whereas ArmA-producing isolates belonged to ST10, ST 167 and ST 117. This first description of 16S rRNA methylases among E. coli in Algerian hospitals pointed out the necessity to establish control measures to avoid their dissemination.

  14. El derecho a la libre autodeterminación de los pueblos y el caso fallido del Sahara Occidental. Los límites del cosmopolitismo y la ecosoberanía como propuesta alternativa

    Directory of Open Access Journals (Sweden)

    Myrna Rodríguez Añuez

    2017-01-01

    Full Text Available El conflicto del Sahara Occidental es un caso pendiente de descolonización en el continente africano. No obstante, su resolución sigue siendo compleja y difusa. Analizamos el caso a la luz del fracaso del cosmopolitismo y proponemos una lectura nueva de la búsqueda de la independencia del Sahara Occidental a partir del concepto de ecosoberanía, por considerarlo un intento teórico de actualizar el derecho a la libre autodeterminación en las condiciones internacionales del siglo XXI.

  15. Estimation of the temperature, heat gain and heat loss by solar parabolic trough collector under Algerian climate using different thermal oils

    International Nuclear Information System (INIS)

    Ouagued, Malika; Khellaf, Abdallah; Loukarfi, Larbi

    2013-01-01

    Highlights: • Estimation of direct solar radiations for different tracking systems at six typical locations in Algeria. • PTC thermal model uses energy balances from the HTF to the atmosphere. • The model depends on the collector type, nature of HTF, optical properties, and ambient conditions. • Estimation of temperature, heat gain and energy cost of thermal oils used in the model. • Comparison between monthly mean heat gain of the various thermal oils for six Algerian locations. - Abstract: Algeria is blessed with a very important renewable, and more particularly solar, energy potential. This potential opens for Algeria reel opportunities to cope with the increasing energy demand and the growing environmental problems link to the use of fossil fuel. In order to develop and to promote concrete actions in the areas of renewable energy and energy efficiency, Algeria has introduced a national daring program for the period 2011–2030. In this program, solar energy, and more particularly solar thermal energy plays an important role. In this paper, the potential of direct solar irradiance in Algeria and the performance of solar parabolic trough collector (PTC) are estimated under the climate conditions of the country. These two factors are treated as they play an important role in the design of solar thermal plant. In order to determine the most promising solar sites in Algeria, monthly mean daily direct solar radiation have been estimated and compared for different locations corresponding to different climatic region. Different tilted and tracking collectors are considered so as to determine the most efficient system for the PTC. In order to evaluate the performance of a tracking solar parabolic trough collector, a heat transfer model is developed. The receiver, heat collector element (HCE), is divided into several segments and heat balance is applied in each segment over a section of the solar receiver. Different oils are considered to determine the thermal

  16. ‘Everybody knows’, but the rest of the world: the case of a caterpillar-borne reproductive loss syndrome in dromedary camels observed by Sahrawi pastoralists of Western Sahara

    NARCIS (Netherlands)

    Volpato, G.; Nardo, Di A.; Rossi, D.; Lamin Saleh, S.; Broglia, A.

    2013-01-01

    Background The traditional knowledge of local communities throughout the world is a valuable source of novel ideas and information to science. In this study, the ethnoveterinary knowledge of Sahrawi pastoralists of Western Sahara has been used in order to put forward a scientific hypothesis

  17. The Double Burden of Obesity and Malnutrition in a Protracted Emergency Setting: A Cross-Sectional Study of Western Sahara Refugees

    Science.gov (United States)

    Grijalva-Eternod, Carlos S.; Wells, Jonathan C. K.; Cortina-Borja, Mario; Salse-Ubach, Nuria; Tondeur, Mélody C.; Dolan, Carmen; Meziani, Chafik; Wilkinson, Caroline; Spiegel, Paul; Seal, Andrew J.

    2012-01-01

    Background Households from vulnerable groups experiencing epidemiological transitions are known to be affected concomitantly by under-nutrition and obesity. Yet, it is unknown to what extent this double burden affects refugee populations dependent on food assistance. We assessed the double burden of malnutrition among Western Sahara refugees living in a protracted emergency. Methods and Findings We implemented a stratified nutrition survey in October–November 2010 in the four Western Sahara refugee camps in Algeria. We sampled 2,005 households, collecting anthropometric measurements (weight, height, and waist circumference) in 1,608 children (6–59 mo) and 1,781 women (15–49 y). We estimated the prevalence of global acute malnutrition (GAM), stunting, underweight, and overweight in children; and stunting, underweight, overweight, and central obesity in women. To assess the burden of malnutrition within households, households were first classified according to the presence of each type of malnutrition. Households were then classified as undernourished, overweight, or affected by the double burden if they presented members with under-nutrition, overweight, or both, respectively. The prevalence of GAM in children was 9.1%, 29.1% were stunted, 18.6% were underweight, and 2.4% were overweight; among the women, 14.8% were stunted, 53.7% were overweight or obese, and 71.4% had central obesity. Central obesity (47.2%) and overweight (38.8%) in women affected a higher proportion of households than did GAM (7.0%), stunting (19.5%), or underweight (13.3%) in children. Overall, households classified as overweight (31.5%) were most common, followed by undernourished (25.8%), and then double burden–affected (24.7%). Conclusions The double burden of obesity and under-nutrition is highly prevalent in households among Western Sahara refugees. The results highlight the need to focus more attention on non-communicable diseases in this population and balance obesity prevention

  18. NEW JULY SAHARA

    African Journals Online (AJOL)

    Winnie

    affected by HIV and AIDS, and that the more food- secure households are those in which both genders are involved in diverse agricultural practices, little is known about the gender context of households that are able to cope with the impact and recover from food insecurity. The text ends with a discussion of HIV and AIDS in.

  19. NEW JULY SAHARA

    African Journals Online (AJOL)

    Winnie

    Africa, routine prevention is hardly ever evaluated and when studies on prevention are ... She has done extensive fieldwork in Senegal, participating in socio-demographic qualitative and quantitative surveys. She has a longstanding interest ..... knowledge score, thinking that condoms protect against. AIDS, and thinking that ...

  20. NEW JULY SAHARA

    African Journals Online (AJOL)

    Winnie

    She has carried out extensive research in various public health-related issues including HIV/AIDS, drinking and driving, substance use and misuse, suicide prevention and sanitation promotion. Karl Peltzer is a Chief Research Specialist at the Social Aspects of HIV/AIDS and Health of the Human Sciences Research Council ...

  1. SAHARA MAKEUP NOV 07

    African Journals Online (AJOL)

    Winnie

    Respondents had high perceived levels of risk.They reported making various behavioural changes to avoid GBV.The respondents were aware of their legal rights pertaining to. GBV. HIV/AIDS ...... give some indication of the openness and acceptance of the different conditions. It could be argued that women would be less ...

  2. SAHARA MAKEUP NOV 07

    African Journals Online (AJOL)

    Winnie

    frequency of male circumcision and of its association with HIV.There are very few attempts to understand the conceptual and philosophical aspects and the broader social and cultural dynamics involved.Thus strictly biomedical approaches may encounter problems of acceptability and of sustainability in local cultures. It.

  3. NEW JULY SAHARA

    African Journals Online (AJOL)

    Winnie

    West Kenya since 2001, in partnership with communities in Bondo and Rachuonyo Districts, Kenya. ABC O Ayayo is Professor of .... service before exit. Findings indicated that 68% of the participants received less than 5 minutes of post-test counselling, 21% had 5 - 10 minutes, and only 10.7% had more than 10 minutes of ...

  4. NEW JULY SAHARA

    African Journals Online (AJOL)

    Winnie

    related events, sentinel .... event of any kind were submitted to inclusion in a forward stepwise process.These analyses were conducted ... their village, deceased, or mentally disabled and could not be interviewed.Another 6 (1% of those present).

  5. SAHARA MAKEUP NOV 07

    African Journals Online (AJOL)

    Winnie

    Mots clés: CDV,VIH, genre. Kennedy Otwombe is currently a PhD student in statistics at the University of the Witwatersrand with an interest in the application of statistics in health research. His current interest is in monitoring and evaluation of HIV related studies and the analysis of incomplete data in longitudinal studies.

  6. SAHARA MAKEUP NOV 07

    African Journals Online (AJOL)

    Winnie

    with HIV/AIDS, 66% of females and males were in the age group 21-40 years, while 10% were older people ..... older than them. In many societies, women cannot insist on condom use or refuse sexual advances from their partners, even if they are young or know that ..... per week on drugs not to talk of eating good food.

  7. NEW JULY SAHARA

    African Journals Online (AJOL)

    Winnie

    three case studies of companies, each with over 20 000 South African-based employees, we identify six 'drivers' .... employees.The companies, representing a convenience sample, were researched between 2001 and 2004.A total of some 280 in-depth interviews were ..... position itself as an integral part of the new South.

  8. Impact of MTHFR rs1801133, MTHFR rs1801131 and ABCB1 rs1045642 polymorphisms with increased susceptibility of rheumatoid arthritis in the West Algerian population: A case-control study.

    Directory of Open Access Journals (Sweden)

    Wefa BOUGHRARA

    2015-10-01

    Full Text Available Rheumatoid arthritis (RA is an autoimmune disease that results in a chronic systemic inflammation. A few genetic epidemiologic studies found a potential association between genetic polymorphisms C677T (rs1801133 and A1298C (rs1801131 of methylenetatrahydrofolate reductase (MTHFR gene and C3435T (rs1045642 of ATP-Binding cassette (ABCB1 gene and the increased risk for RA. The aim of this case-control study was to determine the relationship between these polymorphisms and RA susceptibility in West Algerian population. The dataset of the current study is composed of 110 RA patients and 101 healthy controls. All samples were genotyped for theses polymorphisms by TaqMan® allelic discrimination assay. Data were compared between cases and controls by the calculation of the odds ratio (OR with a confidence interval at 95%. After age and RA erosion-stratified analyzes, no differences in genotypes or alleles frequencies distribution were found for MTHFR C677T (rs1801133 and ABCB1 C3435T (rs1045642 polymorphisms between RA cases and controls. However, the MTHFR A1298C (rs1801131 polymorphism presented a significant distribution in RA with age ≥ 40 (Genotypic data: p=0.007, OR=13.53[1.44-63.31], Allelic data: p=0.001, OR=2.39[1.39-4.1], and in RA erosive form (Genotypic data: p=0.002, OR=6.92[1.68-30.23], Allelic data: p=0.0001, OR=2.43[1.54-3.85].These results were confirmed after the Bonferroni correction. In this study we have showed, for the first time in the West Algerian population, that the MTHFR A1298C (rs1801131 polymorphism can be associated with rheumatoid arthritis.

  9. Relict populations of Diaphanosoma  (Cladocera: Ctenopoda) in the Chadian Sahara, with the description of a new species .

    Science.gov (United States)

    Guo, Fei-Fei; Dumont, Henri J

    2014-08-21

    We record two species of Diaphanosoma from Ounianga and Tibesti in Northern Chad, the first ctenopods to be found in the Sahara desert. One species, from a freshwater guelta on the south flanks of the Tibesti (D. excisum) is tropical; the second species, found in a freshwater lake in a largely saline environment (the Ounianga plateau) is new to science (D. bopingi sp.nov.) and is here described, with special attention to some previously unnoticed structures on the postabdomen. Its relatives are northern species that may transgress into the tropics but largely live outside of them. They are also more salt-tolerant than the tropical D. excisum. The latter is considered a relict of Megachad times, while the new species is considered a relict of more humid but also cooler times in the desert. 

  10. High and Medium Resolution Satellite Imagery to Evaluate Late Holocene Human–Environment Interactions in Arid Lands: A Case Study from the Central Sahara

    Directory of Open Access Journals (Sweden)

    Stefano Biagetti

    2017-04-01

    Full Text Available We present preliminary results of an Earth observation approach for the study of past human occupation and landscape reconstruction in the Central Sahara. This region includes a variety of geomorphological features such as palaeo-oases, dried river beds, alluvial fans and upland plateaux whose geomorphological characteristics, in combination with climate changes, have influenced patterns of human dispersal and sociocultural activities during the late Holocene. In this paper, we discuss the use of medium- and high-resolution remotely sensed data for the mapping of anthropogenic features and paleo- and contemporary hydrology and vegetation. In the absence of field inspection in this inaccessible region, we use different remote sensing methods to first identify and classify archaeological features, and then explore the geomorphological factors that might have influenced their spatial distribution.

  11. PALEODRAINAGES OF THE EASTERN SAHARA - THE RADAR RIVERS REVISITED (SIR - A/B IMPLICATIONS FOR A MID - TERTIARY TRANS - AFRICAN DRAINAGE SYSTEM).

    Science.gov (United States)

    McCauley, John F.; Breed, Carlos S.; Schaber, Gerald G.; McHugh, William P.; Issawi, Bahay; Haynes, C. Vance; Grolier, Maurice J.; El Kilani, Ali

    1986-01-01

    A complex history of Cenozoic fluvial activity in the presently hyperarid eastern Sahara is inferred from Shuttle Imaging Radar (SIR) data and postflight field investigations in southwest Egypt and northwest Sudan. SIR images were coregistered with Landsat and existing maps as a guide to exploration of the buried paleodrainages (radar rivers) first discovered by SIR-A. Field observations explain the radar responses of three types of radar rivers: RR-1, RR-2, and RR-3. A generalized model of the radar rivers, based on field studies and regional geologic relations, shows apparent changes in river regimen since the large valleys were established during the late Paleogene-early Neogene eras. SIR-based mapping of these paleodrainages, although incomplete, reveals missing links in an area once thought to be devoid of master streams.

  12. Siderophile element distribution in metal-sulfide nodules of EH3 Sahara 97072: A relict condensation signature overprinted by transient melting events

    Science.gov (United States)

    Lehner, S. W.; Buseck, P.; McDonough, W. F.; Ash, R.

    2008-12-01

    Evidence of a condensation signature has been detected in the textures and compositions of metal-sulfide nodules (MSN) from the unequilibrated enstatite chondrite Sahara 97072 (EH3). There are two end-member models, both of which can reproduce the siderophile element relations and distribution among the kamacite (αFeNi), schreibersite (FeNiP3), and perryite [(FeNi)x(SiP)y] observed in the MSN. These minerals may have condensed as a single metal alloy that subsequently decomposed in transient melting events or they could have condensed as separate phases. Most likely the minerals were produced from some combination of both processes. Kamacite, schreibersite, and perryite compositions in MSN can reasonably be recombined to produce a metallic phase with Co/Ni and P/Ni ratios similar to those in primitive CI meteorites. The recombined metal has siderophile element (Ir, Ru, Co, Pd, Au, Ga,) ratios closer to CI values than kamacite alone, suggesting it could have been a condensing metal that remained in equilibrium with a cooling reduced gas of near solar composition until Au and Ga condensed. Alternatively, nearly CI chondritic Pd/Ru ratios in schreibersite suggest it could be an early condensate. Perryite may have initially formed as a condensate, as a product of metal sulfurization, or both, but, if so, it appears to also have re-crystallized from a liquid rich in Ni and Si during partial melting of the MSN. Fe, Ni, and P distributions in kamacite near perryite and schreibersite suggest they are primitive minerals in disequilibrium with the metal, indicating they formed in transient melting events as opposed to slow metamorphic heating. The siderophile element distribution in Sahara 97072 MSN is consistent with early condensing material that was later reprocessed by transient melting events.

  13. Trends and challenges towards integration of traditional medicine in formal health care system: Historical perspectives and An Appraisal of education curricula in Sub-Sahara Africa

    Directory of Open Access Journals (Sweden)

    Ester Innocent

    2016-09-01

    Full Text Available The population residing Sub Sahara Africa (SSA continues to suffer from communicable health problems such as HIV/AIDS, Malaria, Tuberculosis, various Neglected Tropical as well as Non-Communicable Diseases. The disease burden is aggravated by shortage of medical personnel and medical supplies such as medicine and medical devices. Also, the population in most countries in this region still and has minimal access to essential medicine. For long time, human beings through observation and practical experiences learned to use different plant species that led to the emergence of traditional medicine (TM systems. The ancient Pharaonic Egyptian traditional medicine system is one of the oldest documented form of traditional medicine practice in Africa and the pioneer of world’s medical science. However, the medical practices diffused very fast to other continents being accelerated by advancement of technologies while leaving Africa lagging behind in the integration of the practice in formal health care system. Challenging issues that drags back integration is the development of education curricula for training Traditional medicine experts as the way of disseminating the traditional medical knowledge and practices imbedded in African culture. The few African countries such as Ghana has managed to integrate TM products in the National Essential Medicine List while South Africa, Sierra Leone and Tanzania have traditional medicine products being sold over the counters due to availability of education training programs facilitated by research. This paper analyses the contribution of TM practice and products in modern medicine and gives recommendations that Africa should taken in the integration process in order to safeguard the Sub-Sahara Africa population from disease burdens [J Complement Med Res 2016; 5(3.000: 312-316

  14. Sr, Nd and Pb Isotope Systematics of the Cenozoic Volcanism in the Algerian Tell Belt: a Key Constraint on the Geodynamic Evolution of the Westernmost Mediterranean

    Science.gov (United States)

    Meddi, Yassamina; Garrido, Carlos J.; Marchesi, Claudio; Louni-Hacini, Amina; Azzouni-Sekkal, Abla; Varas Reus, María Isabel; Harvey, Jason; Hidas, Károly

    2017-04-01

    The geodynamic evolution of the Western Mediterranean is closely linked to the spatio-temporal evolution of the Cenozoic magmatism in this region. Here, we present a detailed Sr-Nd-Pb study of Cenozoic volcanism from the external and the internal zones of the Algerian Tell belt, a segment of paramount importance to unravel the Alpine geodynamic evolution of the westernmost Mediterranean. The age of the studied volcanics rocks ranges from 17 to 3 Ma, and covers the temporal and spatial evolution of magmatism from calc-alkaline rocks with a clear signature of subduction (commonly referred as to orogenic magmatism), followed by progressively younger sub-alkaline and alkaline volcanism. On the basis of their major and trace element composition, the Tell Cenozoic volcanic rocks can be classified into three main groups: (1) a Si-poor group that is composed of basalt, trachybasalt and basaltic trachyandesite; (2) a Si-intermediate group —raging in silica from 56 to 66 wt. %— that is composed of andesite, dacite, trachyandesite et trachydacite; and a (3) Si-rich group —with silica contents generally greater than 66 wt.%— that is constituted by trachydacite, dacite and rhyolite. The Si-poor group occurs only in the External zone and it is characterized by non-radiogenic 87Sr/86Sr ratios, high initial 144Nd/143Nd ratios, significant variation of 206Pb/204Pb and 207Pb/204Pb ratios, and relatively constant 208Pb/204Pb ratios. The Si-intermediate and Si-rich groups from the Internal and External zones show substantial differences. The 206Pb/204Pb ratios of External zone volcanism are relatively constants [18.68-18.86], while they vary significantly in the Internal zone volcanism [18.55-18.92]. On the other hand, the initial 207Pb/204Pb and 208Pb/204Pb ratios in Internal zone volcanism [38.81-38.95] are significantly higher than those of the External zone [38.68-38.84]. These differing isotopic signatures reflect variable source contamination by subducted sediments

  15. Temperature profiles from STD casts from the Spanish Sahara from NOAA Ship OCEANOGRAPHER as part of the International Decade of Ocean Exploration / Coastal Upwelling Ecosystems Analysis (IDOE/CUEA) from 1974-03-08 to 1974-05-01 (NODC Accession 9800112)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profiles were collected from STD casts off the Spanish Sahara from NOAA Ship OCEANOGRAPHER from 08 March 1974 to 01 May 1974. Data were collected by the...

  16. Healing war wounds and perfuming exile: the use of vegetal, animal, and mineral products for perfumes, cosmetics, and skin healing among Sahrawi refugees of Western Sahara.

    Science.gov (United States)

    Volpato, Gabriele; Kourková, Pavlína; Zelený, Václav

    2012-12-27

    Over the past decade, there has been growing interest within ethnobiology in the knowledge and practices of migrating people. Within this, scholars have given relatively less attention to displaced people and refugees: to the loss, maintenance, and adaptation of refugees' ethnobiological knowledge, and to its significance for refugees' wellbeing. This study focuses on cosmetics and remedies used to heal skin afflictions that are traditionally used by Sahrawi refugees displaced in South Western Algerian refugee camps. The research methods included a structured survey carried out with 37 refugee households, semi-structured interviews with 77 refugees, 24 retrospective interviews with refugees and other knowledgeable informants, and a voucher specimen collection of the plants and products cited. We recorded the use of 55 plant species, nine animal species, and six mineral products used within the three main use categories discussed in this paper: 1) Remedies for health issues that are typical of the desert environment where the Sahrawi once lived as nomads and now live as refugees (e.g. eye afflictions); 2) Remedies for wounds that are influenced by the Sahrawi's recent history of guerrilla warfare; and 3) Cosmetics and products used for body care, decoration and perfuming (e.g. hair care, teeth cleansing, henna use) and for aromatizing the air inside of tents and which are widely used in everyday life and social practices. We discuss the changes that have occurred in the patterns of use and procurement of these products with exile and sedentarization in refugee camps, and conclude that refugees are not simply passive recipients of national and international aid, but rather struggle to maintain and recover their traditional ethnobiological practices in exile. Finally, we suggest further research into the ethnobiological practices and knowledge of displaced populations.

  17. A comparison of the physical properties of desert dust retrieved from the sunphotometer observation of major events in the Sahara, Sahel, and Arabian Peninsula

    KAUST Repository

    Masmoudi, Mohamed

    2015-05-01

    © 2015 Elsevier B.V. The objective of this work is to assess the variability of the size-distribution, real (n) and imaginary (k) parts of the refractive index, asymmetry parameter (g), and single scattering albedo (SSA) of desert dust events observed in the Sahara, Sahel, and Arabian Peninsula areas. For this we use the level-2 inversions of 14 AERONET sunphotometers representative of the area of study. In the dataset, the dust-dominated events are discriminated on the basis of their large optical depth and low (<. 0.3) Ångström exponent (α) calculated between 440. nm and 870. nm. In all the volume size-distributions a coarse mode (CM) of particles is observed but a fine mode (FM) of particles with radii. <. 0.2. μm is also present. The volume fraction represented by the FM is lower (3%) during the most intense dust storms than during moderate ones (12%). The inter-site variability of the characteristics of the CM-dominated situations is found to be non-significant and at 440, 675, 870, and 1020. nm a common set of values can be adopted for n (1.54 ± 0.03, 1.53 ± 0.02, 1.50 ± 0.02, 1.48 ± 0.02), k (0.0037 ± 0.0007, 0.0012 ± 0.0002, 0.0011 ± 0.0002, 0.0012 ± 0.0002), g (0.77 ± 0.01, 0.74 ± 0.01, 0.73 ± 0.01, 0.74 ± 0.01), and the SSA (0.90 ± 0.02, 0.97 ± 0.01, 0.98 ± 0.01, 0.98 ± 0.01). However; during the less intense dust-events the growing influence of the FM leads to regional differentiation of the dust properties and 2 main areas can be distinguished: 1) the relatively clean central Sahara/Sahel, and 2) the more polluted continuum constituted by the Mediterranean coast and the Arabian Peninsula.

  18. Noble gases in D’Orbigny, Sahara 99555 and D’Orbigny glass—Evidence for early planetary processing on the angrite parent body

    Science.gov (United States)

    Busemann, Henner; Lorenzetti, Silvio; Eugster, Otto

    2006-11-01

    We analyzed the spallogenic, trapped, fissiogenic and radiogenic noble gas components in various bulk samples of the angrites D'Orbigny and Sahara 99555 as well as in glass separates of D'Orbigny. The D'Orbigny glass samples show hints of solar-like noble gases, as deduced from the trapped elemental and Ne isotopic compositions; the bulk samples do not contain detectable amounts of trapped gases. These observations indicate that D'Orbigny experienced a complex history shortly after its formation 4.56 Ga ago. The glass of D'Orbigny most likely represents magma that rose from the interior of the angrite parent body (APB) and was quenched near the surface. Hence, the APB may contain—similar to the interior of Earth and Mars—solar noble gases. This would call into question the suggested trapping mechanism for solar noble gases in the Earth and Mars, which involves the solution of early atmospheres into magma oceans, due to the APB's inability to retain a primordial atmosphere. The first detection of—possibly parentless—radiogenic excess 129Xe and solar noble gases in the glass of D'Orbigny indicates that the interior of APB degassed to a lesser degree than the outer regions. Therefore primordially trapped, fossil 129I was kept. The APB was not completely devolatilized. Sahara 99555 yields a cosmic-ray exposure age of 6.8 ± 0.3 Ma, while D'Orbigny was exposed to cosmic rays for 11.9 ± 1.2 Ma. Both ages are different than those found in the other angrites. Hence, the angrites analyzed so far sampled surface material from the APB that was ejected in at least five events. In contrast to the bulk sample, the D'Orbigny glass separates yield concordant ages of only 3.0 ± 1.1 Ma, apparently suggesting a pre-exposure of the host material. However, such a scenario is unlikely, due to very similar Mn-Cr ages found in the bulk and glass of D'Orbigny. Most likely, this discrepancy is the result of additional, secondary gas-free glass. Such glass might have been formed

  19. Gradual aridification of the Sahara during the last 11,000 years revealed by plant wax δD analyses of Lake Yoa (Chad)

    Science.gov (United States)

    Rethemeyer, Janet; Kröpelin, Stefan; Karls, Jens; Thienemann, Matthias; Melles, Martin; Schefuß, Enno

    2014-05-01

    It is still an ongoing debate whether the transition of the last 'green Sahara' period to today's large desert during the Holocene, the African Humid Period (AHP), was a progressive or an abrupt change in hydrological conditions. Several climate records mainly from East Africa suggest a rapid decline of moisture availability at the end of the AHP including new data from a marine sequence off the Horn of Africa (Tierney & deMenocal, 2013). Other archives including sedimentological, geochemical and palynological data from the central North African Lakes Chad and Lake Yoa point to a gradual rather than an abrupt transition near 5,000 years ago (Amaral et al., 2013; Kröpelin et al., 2008). The discrepancy of the available paleo-hydrological reconstructions underline the importance of proxy parameters directly related to hydrological conditions for accurate assessment of continental rainfall changes. Here, we present the first molecular-isotopic data from Lake Yoa documenting the hydrologic evolution over the entire Holocene. Compound-specific carbon and hydrogen isotope analyses were performed on long-chain n-alkanes. Our data indicate relative high but variable contributions of plant-derived long-chain n-alkanes carrying a distinct leaf-wax signature, i.e., a high Carbon Preference Index (CPI). A trend towards higher CPI values since 7,300 years ago suggests declining soil degradation and vegetation cover under increasingly drier conditions. In parallel, the average-chain-length of the long-chain n-alkanes increases gradually towards the present implying higher relative contributions from grasses. Compound-specific carbon isotope data confirm this finding, indicating a mixed C3/C4 contribution in the early and mid-Holocene changing towards a C4-grass dominated vegetation in the late Holocene. Most importantly, compound-specific hydrogen isotope data reveal a continuous increase from 8,100 years ago towards the present, reflecting a gradual aridification. The large

  20. New early Pliocene owls from Langebaanweg, South Africa, with first evidence of Athene south of the Sahara and a new species of Tyto

    Directory of Open Access Journals (Sweden)

    Marco Pavia

    2015-12-01

    Full Text Available The fossiliferous Upper Varswater Formation at Langebaanweg (South Africa produced remains of at least five species of owls (Strigiformes. Tyto richae sp. nov. is the first palaeospecies of Tytonidae described from an African fossil site, though indeterminate remains referable to the genus Tyto are known from the Middle Miocene of Morocco, the early Pliocene of Ethiopia, and the Pliocene of Tanzania. Athene inexpectata sp. nov. is not only the earliest documented fossil evidence for the genus worldwide, but also the first record of a species of Athene in Africa south of the Sahara. Proportions of its hind limb indicate that At. inexpectata sp. nov. probably has been as terrestrial as its modern relative At. cunicularia. A few additional remains represent the earliest fossil evidence for the genera Asio and Bubo on the African continent, though the poor preservation of these bones prevents more detailed identifications. A distal tibiotarsus of a small owl about the size of At. inexpectata sp. nov. indicates the presence of a fifth, as yet indeterminate, species of owl at Langebaanweg. Biogeographical and palaeoecological implications of this assemblage of owls are discussed.

  1. Diagnosis of the Relationship between Dust Storms over the Sahara Desert and Dust Deposit or Coloured Rain in the South Balkans

    Directory of Open Access Journals (Sweden)

    N. G. Prezerakos

    2010-01-01

    Full Text Available The main objects of study in this paper are the synoptic scale atmospheric circulation systems associated with the rather frequent phenomenon of coloured rain and the very rare phenomenon of dust or sand deposits from a Saharan sandstorm triggered by a developing strong depression. Analysis of two such cases revealed that two days before the occurrence of the coloured rain or the dust deposits over Greece a sand storm appeared over the north-western Sahara desert. The flow in the entire troposphere is southerly/south-westerly with an upward vertical motion regime. If the atmospheric conditions over Greece favour rain then this rain contains a part of the dust cloud while the rest is drawn away downstream adopting a light yellow colour. In cases where the atmospheric circulation on the route of the dust cloud trajectories is not intensively anticyclonic dust deposits can occur on the surface long far from the region of the dust origin. Such was the case on 4th April, 1988, when significant synoptic-scale subsidence occurred over Italy and towards Greece. The upper air data, in the form of synoptic maps, illustrate in detail the synoptic-scale atmospheric circulations associated with the emission-transport-deposition and confirm the transportation of dust particles.

  2. Surviving in mountain climate refugia: new insights from the genetic diversity and structure of the relict shrub Myrtus nivellei (Myrtaceae in the Sahara Desert.

    Directory of Open Access Journals (Sweden)

    Jérémy Migliore

    Full Text Available The identification of past glacial refugia has become a key topic for conservation under environmental change, since they contribute importantly to shaping current patterns of biodiversity. However, little attention has been paid so far to interglacial refugia despite their key role for the survival of relict species currently occurring in climate refugia. Here, we focus on the genetic consequences of range contraction on the relict populations of the evergreen shrub Myrtus nivellei, endemic in the Saharan mountains since at least the end of the last Green Sahara period, around 5.5 ka B.P. Multilocus genotypes (nuclear microsatellites and AFLP were obtained from 215 individuals collected from 23 wadis (temporary rivers in the three main mountain ranges in southern Algeria (the Hoggar, Tassili n'Ajjer and Tassili n'Immidir ranges. Identical genotypes were found in several plants growing far apart within the same wadis, a pattern taken as evidence of clonality. Multivariate analyses and Bayesian clustering revealed that genetic diversity was mainly structured among the mountain ranges, while low isolation by distance was observed within each mountain range. The range contraction induced by the last episode of aridification has likely increased the genetic isolation of the populations of M. nivellei, without greatly affecting the genetic diversity of the species as a whole. The pattern of genetic diversity observed here suggests that high connectivity may have prevailed during humid periods, which is consistent with recent paleoenvironmental reconstructions.

  3. Trends and challenges toward integration of traditional medicine in formal health-care system: Historical perspectives and appraisal of education curricula in Sub-Sahara Africa

    Science.gov (United States)

    Innocent, Ester

    2016-01-01

    The population residing Sub-Sahara Africa (SSA) continues to suffer from communicable health problems such as HIV/AIDS, malaria, tuberculosis, and various neglected tropical as well as non-communicable diseases. The disease burden is aggravated by shortage of medical personnel and medical supplies such as medical devices and minimal access to essential medicine. For long time, human beings through observation and practical experiences learned to use different plant species that led to the emergence of traditional medicine (TM) systems. The ancient Pharaonic Egyptian TM system is one of the oldest documented forms of TM practice in Africa and the pioneer of world’s medical science. However, the medical practices diffused very fast to other continents being accelerated by advancement of technologies while leaving Africa lagging behind in the integration of the practice in formal health-care system. Challenging issues that drag back integration is the development of education curricula for training TM experts as the way of disseminating the traditional medical knowledge and practices imbedded in African culture. The few African countries such as Ghana managed to integrate TM products in the National Essential Medicine List while South Africa, Sierra Leone, and Tanzania have TM products being sold over the counters due to the availability of education training programs facilitated by research. This paper analyses the contribution of TM practice and products in modern medicine and gives recommendations that Africa should take in the integration process to safeguard the SSA population from disease burdens. PMID:27366358

  4. WESTERN SAHARA AND THE INTERNATIONAL SECURITY SYSTEM. Power relations in the open. What would be the role of the international right?

    Directory of Open Access Journals (Sweden)

    JAIME ABEDRAPO ROJAS

    2017-09-01

    Full Text Available The self-proclamation of independence of the Saharawi nation was recognized by 72 states, and after that, Western Sahara was admitted in the UAO during 1982. Nevertheless, the failed negotiations between Morocco and the Polisary Front have influenced the no application of the International Judicial Court’s resolution, keeping in status quo the self-determination of the recognized Saharawi nation. At the same time, the political support for the recognition of the Saharawi, since the withdrawal of the Spanish occupation in the seventies has reduced, because, nowadays several countries have retired its support to the state-building project. The Moroccan and American strategies as a warrant of the negotiation process have been one of stop and delay the making of a referendum that may allow the manifest of the will of the Saharawis in respect of their destiny as a nation. In fact, every day is more difficult to make such referendum, because the native population composition has been altered, situation that make unfeasible the creation of an electorate register system, and thus setting away the application of the international law, that through the International Court of Justice had recognized the existence of a nation, with a right of self-determination still kept on hold, and seeming that will still be kept in the future with no changes.

  5. Trends and challenges toward integration of traditional medicine in formal health-care system: Historical perspectives and appraisal of education curricula in Sub-Sahara Africa.

    Science.gov (United States)

    Innocent, Ester

    2016-01-01

    The population residing Sub-Sahara Africa (SSA) continues to suffer from communicable health problems such as HIV/AIDS, malaria, tuberculosis, and various neglected tropical as well as non-communicable diseases. The disease burden is aggravated by shortage of medical personnel and medical supplies such as medical devices and minimal access to essential medicine. For long time, human beings through observation and practical experiences learned to use different plant species that led to the emergence of traditional medicine (TM) systems. The ancient Pharaonic Egyptian TM system is one of the oldest documented forms of TM practice in Africa and the pioneer of world's medical science. However, the medical practices diffused very fast to other continents being accelerated by advancement of technologies while leaving Africa lagging behind in the integration of the practice in formal health-care system. Challenging issues that drag back integration is the development of education curricula for training TM experts as the way of disseminating the traditional medical knowledge and practices imbedded in African culture. The few African countries such as Ghana managed to integrate TM products in the National Essential Medicine List while South Africa, Sierra Leone, and Tanzania have TM products being sold over the counters due to the availability of education training programs facilitated by research. This paper analyses the contribution of TM practice and products in modern medicine and gives recommendations that Africa should take in the integration process to safeguard the SSA population from disease burdens.

  6. Early to Middle Holocene landscape exploitation in a drying environment: Two case studies compared from the central Sahara (SW Fezzan, Libya)

    Science.gov (United States)

    Cremaschi, Mauro; Zerboni, Andrea

    2009-08-01

    The erg Uan Kasa and the wadi Tanezzuft (Libyan Sahara) reacted in different ways to Holocene climatic changes. Consequently, the human groups settled there responded with different ways of adaptation to the drying environment. In the erg Uan Kasa, shallow lakes were formed from the Early to the Mid-Holocene, and their shores were densely inhabited from the Epipalaeolithic to the Pastoral-Neolithic periods. The erg dried out at c. 5000 years BP, but the area was not completely abandoned, as indicated by minor Late Pastoral-Neolithic sites composed of scattered fireplaces. During the wet Holocene, the wadi Tanezzuft was a large meandering river, and its banks were densely settled. At c. 5000 years BP, the stream was not completely dried out, but it changed its pattern, originating an alluvial plain. A large oasis was formed between c. 4000 and 2000 years BP, exploited by Late Pastoral-Neolithic pastoral communities, and later by Garamantians, which introduced soil management and agricultural practices. The Tanezzuft oasis suffered a drastic reduction in size during the first centuries AD, at the time of the abandonment of the Garamantian settlements.

  7. Le développement humain local dans les contextes de crise permanente : l’expérience des femmes au Sahara Occidental

    Directory of Open Access Journals (Sweden)

    María López Belloso

    2009-04-01

    Full Text Available Les femmes sahraouies sont des agents actifs dans la dynamique sociale des camps de réfugiés, au sein desquels elles ont défini un certain nombre de stratégies de résolution de problèmes pour surmonter les obstacles liés à une situation humanitaire qui se détériore. Depuis le début du conflit et le déplacement forcé à Tindouf, en Algérie, les femmes sont en e%et intégralement responsables de la gestion des camps de réfugiés, et ont assumé un rôle de dirigeantes dans de nombreux secteurs de la société. Cet article souligne la contribution des femmes sahraouies au processus de développement humain local dans un contexte de refuge prolongé tel celui que connaît le Sahara Occidental. En plus d’améliorer la capacité d’accès des réfugiés aux ressources matérielles, physiques, sociales et organisationnelles ainsi qu’aux forces motivationnelles, les femmes sahraouies ont été en mesure de mettre en place leur propre processus de renforcement des capacitésII individuelle et collective dans la vie du camp.

  8. The experience of an United Nations Military Observer in Western Sahara / A experiência de observador militar da ONU no Saara Ocidental

    Directory of Open Access Journals (Sweden)

    Sylvio de Souza Ferreira

    2017-03-01

    Full Text Available The Western Sahara issue is the most recent, lasting and unresolved case of decolonization in African continent, in the midst of the 21st Century. It is a non- governed territory, located in the northwest portion of Saharan Africa and it has been under UN custody since 1991, when MINURSO had been established. In this regard, this article has as main motivation to communicate the experience of an UN Military Observer, emphasizing peculiar and practical aspects, as well as perceptions in the performance of this appointment. It is an internal vision of the reality of the Peace Operation, the individual and the professional of the UN. In order to do so, this article uses a qualitative approach deploying methodologies such as participant observation and the descriptive case study. It comprises an introduction, which aims to enlighten the reader to the question, a characterization of the area, a historical review of the case, a section of exposure of the methodology and the experience of one of the authors as a UN Military Observer in the Western Sahara itself. Finally, considerations are made at the conclusion. A questão do Saara Ocidental constitui o caso de descolonização mais recente, duradouro e não-resolvido do continente africano, em pleno século XXI. Trata-se de um território não-governado, localizado na porção noroeste da África Saariana e encontra-se sob custódia da ONU desde 1991, quando da implantação da MINURSO. Nesse contexto, o presente artigo tem como principal motivação comunicar a experiência no exercício da função de observador militar da ONU, sublinhando aspectos peculiares e práticos, bem como percepções no desempenho dessa função. É uma visão interna da realidade de uma Operação de Paz, do indivíduo e do profissional da Organização. Para tanto, o artigo utiliza abordagem qualitativa na metodologia empregada e aspectos da observação participante e do estudo de caso descritivo. É composto por uma

  9. Artificial wetlands as tools for frog conservation: stability and variability of reproduction characteristics in Sahara frog populations in Tunisian man-made lakes.

    Science.gov (United States)

    Bellakhal, Meher; Neveu, André; Fertouna-Bellakhal, Mouna; Aleya, Lotfi

    2017-12-01

    Amphibian populations are in decline principally due to climate change, environmental contaminants, and the reduction in wetlands. Even though data concerning current population trends are scarce, artificial wetlands appear to play a vital role in amphibian conservation. This study concerns the reproductive biology of the Sahara frog over a 2-year period in four Tunisian man-made lakes. Each month, gonad state (parameters: K, GSI, LCI), fecundity, and fertility of females (using 1227 clutches) were evaluated in the field under controlled conditions. Clutches were present for 110-130 days at two of the sites, but only for 60-80 days at the other two. Maximum egg laying occurred in May, corresponding to the highest point in the gonad somatic index. Clutch densities were higher in the smaller lakes. Female fecundity was in relation to body size; mean clutch fecundity attained 1416 eggs, with no differences observed according to site. Egg fertility varied over a 1-year period, with a maximum in May followed by a decrease when water temperature was at its highest. Eggs were smaller at the beginning of spawning; maximum size was in May, which might explain the higher fertility, but no maternal influence was detected. Embryonic development was strictly dependent on temperature. The population at each site appeared as a small patch within a metapopulation in overall good health, as shown by the relative temporal stability in reproduction variables. Constructed wetlands may therefore play an important role in the conservation of amphibians, especially in semi-arid zones.

  10. Impact of climate change on the relict tropical fish fauna of central sahara: threat for the survival of adrar mountains fishes, mauritania.

    Directory of Open Access Journals (Sweden)

    Sébastien Trape

    Full Text Available BACKGROUND: Four central Sahara mountainous massifs provide habitats for relict populations of fish. In the Adrar of Mauritania all available data on the presence and distribution of fish come from pre-1960 surveys where five fish species were reported: Barbus pobeguini, Barbus macrops, Barbus mirei, Sarotherodon galilaeus, and Clarias anguillaris. Since 1970, drought has had a severe impact in the Adrar where rainfall decreased by 35%. To investigate whether the relict populations of fish have survived the continuing drought, a study was carried out from 2004 to 2008. METHODOLOGY/PRINCIPAL FINDINGS: An inventory of perennial bodies of water was drawn up using a literature review and analysis of topographical and hydrological maps. Field surveys were carried out in order to locate the bodies of water described in the literature, identify the presence of fish, determine which species were present and estimate their abundance. The thirteen sites where the presence of fish was observed in the 1950s -Ksar Torchane, Ilij, Molomhar, Agueni, Tachot, Hamdoun, Terjit, Toungad, El Berbera, Timagazine, Dâyet el Mbârek, Dâyet et-Tefla, Nkedeï- were located and surveyed. The Ksar Torchane spring -type locality and the only known locality of B. mirei- has dried up at the height of the drought in 1984, and any fish populations have since become extinct there. The Timagazine, Dâyet el Mbârek and Dâyet et-Tefla pools have become ephemeral. The Hamdoun guelta appears to be highly endangered. The fish populations at the other sites remain unchanged. Four perennial pools which are home to populations of B. pobeguini are newly recorded. CONCLUSION/SIGNIFICANCE: The tropical relict fish populations of the Adrar mountains of Mauritania appear to be highly endangered. Of thirteen previously recorded populations, four have become extinct since the beginning of the drought period. New fish population extinctions may occur should low levels of annual rainfall be

  11. Impact of climate change on the relict tropical fish fauna of central sahara: threat for the survival of adrar mountains fishes, mauritania.

    Science.gov (United States)

    Trape, Sébastien

    2009-01-01

    Four central Sahara mountainous massifs provide habitats for relict populations of fish. In the Adrar of Mauritania all available data on the presence and distribution of fish come from pre-1960 surveys where five fish species were reported: Barbus pobeguini, Barbus macrops, Barbus mirei, Sarotherodon galilaeus, and Clarias anguillaris. Since 1970, drought has had a severe impact in the Adrar where rainfall decreased by 35%. To investigate whether the relict populations of fish have survived the continuing drought, a study was carried out from 2004 to 2008. An inventory of perennial bodies of water was drawn up using a literature review and analysis of topographical and hydrological maps. Field surveys were carried out in order to locate the bodies of water described in the literature, identify the presence of fish, determine which species were present and estimate their abundance. The thirteen sites where the presence of fish was observed in the 1950s -Ksar Torchane, Ilij, Molomhar, Agueni, Tachot, Hamdoun, Terjit, Toungad, El Berbera, Timagazine, Dâyet el Mbârek, Dâyet et-Tefla, Nkedeï- were located and surveyed. The Ksar Torchane spring -type locality and the only known locality of B. mirei- has dried up at the height of the drought in 1984, and any fish populations have since become extinct there. The Timagazine, Dâyet el Mbârek and Dâyet et-Tefla pools have become ephemeral. The Hamdoun guelta appears to be highly endangered. The fish populations at the other sites remain unchanged. Four perennial pools which are home to populations of B. pobeguini are newly recorded. The tropical relict fish populations of the Adrar mountains of Mauritania appear to be highly endangered. Of thirteen previously recorded populations, four have become extinct since the beginning of the drought period. New fish population extinctions may occur should low levels of annual rainfall be repeated.

  12. A hydrological-economic model for sustainable groundwater use in sparse-data drylands: Application to the Amtoudi Oasis in southern Morocco, northern Sahara.

    Science.gov (United States)

    Alcalá, Francisco J; Martínez-Valderrama, Jaime; Robles-Marín, Pedro; Guerrera, Francesco; Martín-Martín, Manuel; Raffaelli, Giuliana; de León, Julián Tejera; Asebriy, Lahcen

    2015-12-15

    A hydrological-economic model is introduced to describe the dynamics of groundwater-dependent economics (agriculture and tourism) for sustainable use in sparse-data drylands. The Amtoudi Oasis, a remote area in southern Morocco, in the northern Sahara attractive for tourism and with evidence of groundwater degradation, was chosen to show the model operation. Governing system variables were identified and put into action through System Dynamics (SD) modeling causal diagrams to program basic formulations into a model having two modules coupled by the nexus 'pumping': (1) the hydrological module represents the net groundwater balance (G) dynamics; and (2) the economic module reproduces the variation in the consumers of water, both the population and tourists. The model was operated under similar influx of tourists and different scenarios of water availability, such as the wet 2009-2010 and the average 2010-2011 hydrological years. The rise in international tourism is identified as the main driving force reducing emigration and introducing new social habits in the population, in particular concerning water consumption. Urban water allotment (PU) was doubled for less than a 100-inhabitant net increase in recent decades. The water allocation for agriculture (PI), the largest consumer of water, had remained constant for decades. Despite that the 2-year monitoring period is not long enough to draw long-term conclusions, groundwater imbalance was reflected by net aquifer recharge (R) less than PI+PU (G<0) in the average year 2010-2011, with net lateral inflow from adjacent Cambrian formations being the largest recharge component. R is expected to be much less than PI+PU in recurrent dry spells. Some low-technology actions are tentatively proposed to mitigate groundwater degradation, such as: wastewater capture, treatment, and reuse for irrigation; storm-water harvesting for irrigation; and active maintenance of the irrigation system to improve its efficiency. Copyright

  13. The daytime cycle in dust aerosol direct radiative effects observed in the central Sahara during the Fennec campaign in June 2011

    KAUST Repository

    Banks, Jamie R.

    2014-12-16

    © 2014. American Geophysical Union. All Rights Reserved. The direct clear-sky radiative effect (DRE) of atmospheric mineral dust is diagnosed over the Bordj Badji Mokhtar (BBM) supersite in the central Sahara during the Fennec campaign in June 2011. During this period, thick dust events were observed, with aerosol optical depth values peaking at 3.5. Satellite observations from Meteosat-9 are combined with ground-based radiative flux measurements to obtain estimates of DRE at the surface, top-of-atmosphere (TOA), and within the atmosphere. At TOA, there is a distinct daytime cycle in net DRE. Both shortwave (SW) and longwave (LW) DRE peak around noon and induce a warming of the Earth-atmosphere system. Toward dusk and dawn, the LW DRE reduces while the SW effect can switch sign triggering net radiative cooling. The net TOA DRE mean values range from -9 Wm-2 in the morning to heating of +59 Wm-2 near midday. At the surface, the SW dust impact is larger than at TOA: SW scattering and absorption by dust results in a mean surface radiative cooling of 145Wm-2. The corresponding mean surface heating caused by increased downward LW emission from the dust layer is a factor of 6 smaller. The dust impact on the magnitude and variability of the atmospheric radiative divergence is dominated by the SW cooling of the surface, modified by the smaller SW and LW effects at TOA. Consequently, dust has a mean daytime net radiative warming effect on the atmosphere of 153Wm-2.

  14. Africa tomorrow: The challenge of the future; Overview of a gas Africa; Energy for all; The impact of world energetic transformations on the Algerian economy; Towards a gas Eldorado? To cook and to live; 1,2,3... biogas, the AFG in Africa

    International Nuclear Information System (INIS)

    Icart, Laura

    2016-01-01

    A set of articles first proposes a brief overview of the energetic challenge faced by Africa for its development, and then an overview and discussion of gas production and consumption in North Africa, in Sub-Saharan Africa, in West Africa, in Central Africa, and in South Africa. As access to energy has been defined as a priority for the 2014-2024 decade and is part of the Millennium objectives for development, a third article comments this issue: unequal and vital access, struggle against energy poverty, how Total, Engie and EDF are concerned and involved. The opportunity of gas-cogeneration is evoked. An article discusses the impact of world energetic transformations on the Algerian economy (influence of price decrease on Sonatrach incomes and on trade balance, Algerian strategy in front of energy transition, improvement of energy efficiency, development of renewable energies, possibility of exploitation of shale gas, possibility of a global reform). The next article comments the expected strong increase of the share of natural gas in the African energy mix, and the fact that the Sub-Saharan natural gas production is predicted to be higher than the Russian one in 2040. An article then comments the issue of energy poverty, health risks related to the use of solid fuels in housing for cooking, and the possible alternative provided by LPG. The last articles outline the high potential represented by biogas, notably in rural and isolated areas, and the commitment of AFG's subsidiaries in Africa

  15. Did the demise of Green Sahara play a role in the mid-to-late Holocene megadrought and `missing millennia' in southeast Asian societies?

    Science.gov (United States)

    Griffiths, M. L.; Johnson, K. R.; Pausata, F. S. R.; White, J.; Yang, H.; Henderson, G. M.; Conrad, C.

    2017-12-01

    cooling in the Indo-Pacific Warm Pool, and matches the timing of west African monsoon (WAM) failure. Using fully coupled ocean-atmosphere model simulations, we show that reduced vegetation and increased dust emissions (such as during the Green Sahara demise) cool the Indian Ocean and shift eastward the Walker circulation, causing a weakening of the Indian Summer Monsoon.

  16. A feasible methodology for groundwater resource modelling for sustainable use in sparse-data drylands: Application to the Amtoudi Oasis in the northern Sahara.

    Science.gov (United States)

    Alcalá, Francisco J; Martín-Martín, Manuel; Guerrera, Francesco; Martínez-Valderrama, Jaime; Robles-Marín, Pedro

    2018-03-02

    In a previous paper, the Amtoudi Oasis, a remote area in the northern Sahara in southern Morocco, was chosen to model the dynamics of groundwater-dependent economics under different scenarios of water availability, both the wet 2009-2010 and the average 2010-2011 hydrological years. Groundwater imbalance was reflected by net aquifer recharge (R) less than groundwater allotment for agriculture and urban uses in the average year 2010-2011. Three key groundwater sustainability issues from the hydrologic perspective were raised for future research, which are addressed in this paper. Introducing a feasible methodology for groundwater resource modelling for sustainable use in sparse-data drylands, this paper updates available databases, compiles new databases, and introduces new formulations to: (1) refine the net groundwater balance (W) modelling for years 2009-2010 and 2010-2011, providing the magnitude of net lateral inflow from adjacent formations (R L ), the largest R component contributing to the oasis; (2) evaluate the non-evaporative fraction of precipitation (P) (B) from 1973 onward as a proxy of the potential renewable water resource available for use; and (3) define the critical balance period for variables to reach a comparable stationary condition, as prerequisite for long-term modelling of W. R L was about 0.07-fold P and 0.85-fold R. Historical yearly B-to-P ratios were 0.02 for dry, 0.04 for average, and 0.07 for wet hydrological years; the average yearly P being 124mm. A critical 17-year balance period with stable relative error below 0.1 was defined from the 44-year P and B time-series statistical study. This is the monitoring period proposed for the stationary evaluation of the variables involved in the long-term modelling of W. This paper seeks to offer a feasible methodology for groundwater modelling addressed for planning sustainable water policies in sparse-data drylands. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Ecotoxicological impact assessment of the brine discharges from a desalination plant in the marine waters of the Algerian west coast, using a multibiomarker approach in a limpet, Patella rustica.

    Science.gov (United States)

    Benaissa, Meriem; Rouane-Hacene, Omar; Boutiba, Zitouni; Guibbolini-Sabatier, Marielle E; Faverney, Christine Risso-De

    2017-11-01

    The aim of our study is to evaluate the impact of Bousfer desalination plant brine discharges on the Algerian west coast, on a natural population of the marine gastropod mollusc Patella rustica. The effects of a chronic exposure to such discharges are complex to understand due to the combined effects of environmental physico-chemical parameters (e.g., high salinity) and different pollutants that can modulate the physiological responses of this species to stress. In this context, we assessed the biological effects in a marine species P. rustica, by a multibiomarker approach that provided information on the health status of organisms in response to such an environmental stress. We measured biomarkers in the whole soft tissues of limpets as indicators of neurotoxicity (AChE activity), oxidative stress (CAT, SOD, GR, and GPx activities), biotransformation (GST), oxidative damage (LPO through TBARS levels), and genotoxicity (CSP 3-like activity). In parallel, hydrological parameters were measured in the Bay of Oran, at four selected sites: site H considered as a "hotspot," located at Bousfer desalination plant; two other sites E and W, at the east and the west of H respectively; finally, site R "reference" located in Madragh, which is considered as a remote clean site. Our analyses revealed that the activities of antioxidant defense enzymes reached the highest levels in P. rustica collected from site H. The activation of antioxidant defense system in these organisms translated the alteration of their status health, reflecting a level of environmental disruption generated by the desalination plant brine discharges and the high salinity in this area. We also observed that the tissues of limpets collected from site H as well as the two other sites, E and W, had undergone molecular damage, confirmed by the high levels of CSP 3-like activity. This damage resulted from chronic exposure to environmental conditions, potentially genotoxic, due to the desalination plant

  18. Methyl Methacrylate and Alpha-Methyl Styrene: New Strategy for Synthesis of Bloc Copolymers for Use in Potential Biomedical Applications Generated by an Ecologic Catalyst Called Maghnite (Algerian MMT

    Directory of Open Access Journals (Sweden)

    Moulkheir Ayat

    2016-10-01

    Strategy for Synthesis of Bloc Copolymers for Use in Potential Biomedical Applications Generated by an Ecologic Catalyst called Maghnite (Algerian MMT. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (3: 316-329 (doi: 10.9767/bcrec.11.3.571.316-329 Permalink/DOI: http://doi.org/10.9767/bcrec.11.3.571.316-329

  19. Conflict resolution in Western Sahara

    African Journals Online (AJOL)

    problems instead of simply blaming others. Citizens must choose to hold .... thousand victims throughout the 2000's decade, with a situation of protracted violence in the provinces nearby Algiers and other .... by the king has organised summary processes to clarify and compensate victims of political repression. Nevertheless ...

  20. The Western Sahara conflict I

    African Journals Online (AJOL)

    African Affairs), and John Bolton (former US Assistant Secretary of State for International. Organisations). James Baker managed to bring about direct talks between the two parties and brokered the "Houston Agreement", which includes the following points: 1 1. • Only a limited number of sub-tribal groups will be added to the ...

  1. Geochemistry and hydrogeochemical process of groundwater in the ...

    African Journals Online (AJOL)

    Ground water is the only hydrous resource exploited in the Souf valley of Algerian Sahara. Several techniques and conventional graphical plots were used to define the geochemistry of the aquifer. Based on the ionic components, hydrochemical facies, the factors controlling groundwater chemistry are assessed and defined ...

  2. Ethnobotanical survey of Phoenix dactylifera L. Pollen used for the ...

    African Journals Online (AJOL)

    Background: The Phoenix dactylifera L. (date palm) is known for its traditional medicinal properties across the history of native population in Algerian Sahara. There is a large trend of consumption of date palm pollen preparations in many human infertility cases in our country. However, the validity has not been scientifically ...

  3. Dust radiative effect over Europe, Mediterranean, Sahara and Middle East from a radiative transfer model using BSC-DREAM8b aerosol optical data

    Science.gov (United States)

    Papadimas, Christos; Gkikas, Antonis; Hatzianastassiou, Nikos; Matsoukas, Christos; Kazadzis, Stelios; Basart, Sara; Baldasano, Jose; Vardavas, Ilias

    2013-04-01

    The arid regions of Saharan desert and Middle East are the world's major dust sources. However, dust particles from these areas are transported to nearby regions, through favourable synoptic conditions, even reaching remote locations in Europe or in the Arctic. This transport is very important in numerous aspects. One of its most important effects is on the radiation budget, and more specifically on solar radiation, through the aerosol direct radiative effect (DRE). Previous studies have shown that this effect is great under dust load conditions. Therefore, it is very important to simulate dust transport processes and associated radiative effects. The simulation of dust production, transport and removal is done by numerical models, which however have their own limitations as to the consideration of physical and dynamical processes as well as their initial conditions. On the other hand, the computation of dust DRE is ideally done with radiative transfer models (RTMs), which however imply uncertainties associated with the input aerosol optical properties. The most important aerosol optical properties used in RTMs and climate models are aerosol optical depth (AOD), single scattering albedo (SSA) and asymmetry parameter (AP). The main target of the present study is to reduce the uncertainties of dust DRE by using a detailed spectral RTM and an acknowledged regional and meso-scale model describing the distribution of dust. The combined use of these tools is applied to the region covering the deserts of Sahara, Arabian Peninsula and Middle East, and the neighbouring Mediterranean basin and European continent (extending from 15°N to 60°N and from 21°W to 54°E). The computations are performed on a monthly mean basis, refer to the 11-year period 2000-2010, and quantify the effects of dust on the reflected solar radiation at the top of atmosphere (DRETOA), on the absorbed solar radiation within the atmosphere (DREatmab), and on the downwelling and absorbed solar

  4. Healing war wounds and perfuming exile: the use of vegetal, animal, and mineral products for perfumes, cosmetics, and skin healing among Sahrawi refugees of Western Sahara

    Directory of Open Access Journals (Sweden)

    Volpato Gabriele

    2012-12-01

    Full Text Available Abstract Background Over the past decade, there has been growing interest within ethnobiology in the knowledge and practices of migrating people. Within this, scholars have given relatively less attention to displaced people and refugees: to the loss, maintenance, and adaptation of refugees’ ethnobiological knowledge, and to its significance for refugees’ wellbeing. This study focuses on cosmetics and remedies used to heal skin afflictions that are traditionally used by Sahrawi refugees displaced in South Western Algerian refugee camps. Methods The research methods included a structured survey carried out with 37 refugee households, semi-structured interviews with 77 refugees, 24 retrospective interviews with refugees and other knowledgeable informants, and a voucher specimen collection of the plants and products cited. Results We recorded the use of 55 plant species, nine animal species, and six mineral products used within the three main use categories discussed in this paper: 1 Remedies for health issues that are typical of the desert environment where the Sahrawi once lived as nomads and now live as refugees (e.g. eye afflictions; 2 Remedies for wounds that are influenced by the Sahrawi’s recent history of guerrilla warfare; and 3 Cosmetics and products used for body care, decoration and perfuming (e.g. hair care, teeth cleansing, henna use and for aromatizing the air inside of tents and which are widely used in everyday life and social practices. Conclusions We discuss the changes that have occurred in the patterns of use and procurement of these products with exile and sedentarization in refugee camps, and conclude that refugees are not simply passive recipients of national and international aid, but rather struggle to maintain and recover their traditional ethnobiological practices in exile. Finally, we suggest further research into the ethnobiological practices and knowledge of displaced populations. Resumen Sanando las heridas de

  5. Healing war wounds and perfuming exile: the use of vegetal, animal, and mineral products for perfumes, cosmetics, and skin healing among Sahrawi refugees of Western Sahara

    Science.gov (United States)

    2012-01-01

    Background Over the past decade, there has been growing interest within ethnobiology in the knowledge and practices of migrating people. Within this, scholars have given relatively less attention to displaced people and refugees: to the loss, maintenance, and adaptation of refugees’ ethnobiological knowledge, and to its significance for refugees’ wellbeing. This study focuses on cosmetics and remedies used to heal skin afflictions that are traditionally used by Sahrawi refugees displaced in South Western Algerian refugee camps. Methods The research methods included a structured survey carried out with 37 refugee households, semi-structured interviews with 77 refugees, 24 retrospective interviews with refugees and other knowledgeable informants, and a voucher specimen collection of the plants and products cited. Results We recorded the use of 55 plant species, nine animal species, and six mineral products used within the three main use categories discussed in this paper: 1) Remedies for health issues that are typical of the desert environment where the Sahrawi once lived as nomads and now live as refugees (e.g. eye afflictions); 2) Remedies for wounds that are influenced by the Sahrawi’s recent history of guerrilla warfare; and 3) Cosmetics and products used for body care, decoration and perfuming (e.g. hair care, teeth cleansing, henna use) and for aromatizing the air inside of tents and which are widely used in everyday life and social practices. Conclusions We discuss the changes that have occurred in the patterns of use and procurement of these products with exile and sedentarization in refugee camps, and conclude that refugees are not simply passive recipients of national and international aid, but rather struggle to maintain and recover their traditional ethnobiological practices in exile. Finally, we suggest further research into the ethnobiological practices and knowledge of displaced populations. Resumen Sanando las heridas de guerra y perfumando el

  6. Evaluation of adsorption capacities of humic acids extracted from Algerian soil on polyaniline for application to remove pollutants such as Cd(II), Zn(II) and Ni(II) and characterization with cavity microelectrode.

    Science.gov (United States)

    Terbouche, Achour; Ramdane-Terbouche, Chafia Ait; Hauchard, Didier; Djebbar, Safia

    2011-01-01

    The adsorption capacities of new humic acids isolated from Yakouren forest (YHA) and Sahara (Tamenrasset: THA) soils (Algeria) and commercial humic acid (PFHA) on polyaniline emeraldine base (PEB) were studied at pH 6.6. Also the adsorption of heavy metals such as Cd2+, Zn2+ and Ni2+ on humic acid-polyaniline systems (HA-PEB) was investigated at the same conditions. HA-PEB compounds were characterized by scanning electron microscopy (SEM), infrared spectrometry and cavity microelectrode. In addition, batch adsorption and cavity microelectrode were used in the adsorption study of Cd2+, Zn2+ and Ni2+ on HA-PEB. To develop biocaptors of polluting metals using a cavity microelectrode modified by HA-PEB systems, the adsorption kinetic and adsorption capacity were investigated. The SEM analysis showed that the presence of humic acid affected the PEB surface and caused the formation of a granular morphology. The maximum adsorption capacities (q(max)) of PFHA, THA and YHA determined by adsorption isotherms were 91.31, 132.1 and 151.0 mg/g, respectively. Batch adsorption results showed that q(max) of Cd2+, Zn2+ and Ni2+ on HA-PEB followed the order: THA-PEB > YHA-PEB > PFHA-PEB. The voltammograms obtained with HA-PEB modified cavity microelectrode showed the appearance of new redox couples reflecting the adsorption of HA on PEB. Metal-humic acid-polyaniline voltammograms were characterized by appearance of oxidation-reduction couples or reduction wave corresponding to metal. Finally, the result may be exploited to develop a biocaptor based on the cavity microelectrode amended by THA-PEB and YHA-PEB.

  7. Interpretación del Arte Rupestre Centro-Sahariano: una aproximación al estilo de Cabezas Redondas = Interpretation of Central Sahara Rock Art: an approach to The Round Head style

    Directory of Open Access Journals (Sweden)

    Hugo Alexander van Teslaar

    2015-11-01

    Full Text Available El estudio del arte rupestre sahariano ha comenzado en las últimas décadas a tener una agenda propia dentro de la investigación prehistórica y a despegar como sub-disciplina arqueológica. África ha pasado de ser vista como un continente baldío a apreciarse como una fuente autónoma de cultura, y el Sahara como recipiente de un inmenso legado cultural y artístico del que los investigadores sólo ahora están empezando a comprender en todo su alcance. Este legado cultural y artístico es el objeto de numerosos estudios encaminados a entender los contextos específicos de producción del arte. El estilo característico de Têtes Rondes es el que mayores dificultades de interpretación plantea a los investigadores. Por ello, ocupa una parte importante de este artículo. La carencia en muchos lugares de información contextual (restos materiales que ayudaría a validar o refutar las hipótesis de los investigadores y lo importante y necesario que resulta para el estudio del arte no quedarse en la lectura «superficial» de las imágenes, son algunos de los aspectos que veremos. Este artículo sostiene que para superar algunos de estos problemas es esencial el uso de enfoques y planteamientos interpretativos abiertos, permitiendo así que las premisas de las que parten los investigadores no estén encorsetadas desde sus inicios por una u otra corriente teórica. Adaptar las teorías interpretativas a los vestigios arqueológicos y no al revés resulta fundamental para mejorar nuestro conocimiento de los tiempos pretéritos.In the last decades the study of Sahara rock art begun to have its own agenda within prehistoric research and to take off as an archaeological sub-discipline. Africa has gone from being seen as an empty continent to an autonomous source of culture, and the Sahara as a container of an immense cultural and artistic legacy whose scope researchers are only now starting to comprehend. This cultural and

  8. COMPANIES GROUPINGIN ALGERIAN AND COMPARATIVE LAW

    Directory of Open Access Journals (Sweden)

    H’oriya SOUIKI

    2017-12-01

    Full Text Available A business cluster is the merging of two businesses or more, under the authority of one company called the parent company; the companies under its control are called the affiliates. What raises the debate about business clustering is the contradiction that may appear, at first glance, in the modus operandi of this business cluster and the relationship existing between its structures, knowing that the affiliated company has a legal independent status, but is at the same time subordinate to the parent company and subject to its control. The absence of an independent and detailed legal text to organize the mysteries of this giant economic structure makes this debate more intense.

  9. Screening of autochthonous Lactobacillus species from Algerian ...

    African Journals Online (AJOL)

    intestinal microflora. Food contamination by Staphylococcus aureus is a major problem for consumer's health in Algeria, especially during the summer period. The use of bacterial interactions is a new way to limit the pathogenic germs growth.

  10. Strong Algerian Earthquake Strikes Near Capital City

    Science.gov (United States)

    Ayadi, A.; Maouche, S.; Harbi, A.; Meghraoui, M.; Beldjoudi, H.; Oussadou, F.; Mahsas, A.; Benouar, D.; Heddar, A.; Rouchiche, Y.; Kherroubi, A.; Frogneux, M.; Lammali, K.; Benhamouda, F.; Sebaï, A.; Bourouis, S.; Alasset, P. J.; Aoudia, A.; Cakir, Z.; Merahi, M.; Nouar, O.; Yelles, A.; Bellik, A.; Briole, P.; Charade, O.; Thouvenot, F.; Semane, F.; Ferkoul, A.; Deramchi, A.; Haned, S. A.

    On 21 May 2003, a damaging earthquake of Mw 6.8 struck the region of Boumerdes 40 km east of Algiers in northern Algeria (Figure 1). The mainshock, which lasted ~ 36-40 s, had devastating effects and claimed about 2300 victims, caused more than 11,450 injuries, and left about 200,000 people homeless. It destroyed and seriously damaged around 180,000 housing units and 6000 public buildings with losses estimated at $5 billion. The mainshock was widely felt within a radius of ~ 400 km in Algeria. To the north, the earthquake was felt in southeastern Spain, including the Balearic Islands, and also in Sardinia and in southern France. The mainshock location, which was calculated at 36.91°N, 3.58°E (15 km offshore of Zemmouri; Figure 1), and the local magnitude (Md 6.4) are from seismic records of local stations. International seismological centers obtained Mw 6.8 (NEIC) with a thrust focal mechanism solution and 1.83 × 1026 dyne.cm for the seismic moment. A sequence of aftershocks affected the epicentral area with two strong shocks reaching Mw 5.8 on 27 and 29 May 2003. Field investigations allowed us to assign a maximum intensity X (European Macroseismic Scale 98) and to report rockfalls, minor surface cracks, and liquefaction phenomena. The mainshock was not associated with inland surface faulting, but one of the most striking coseismic effects is the coastal uplift and the backwash along the littoral of the Mitidja basin.

  11. Screening of autochthonous Lactobacillus species from Algerian ...

    African Journals Online (AJOL)

    AJB2

    2012-03-08

    intestinal microflora. Food contamination by Staphylococcus aureus is a major problem for consumer's health in Algeria, especially during the summer period. The use of bacterial interactions is a new way to limit the pathogenic ...

  12. ‘Everybody knows’, but the rest of the world: the case of a caterpillar-borne reproductive loss syndrome in dromedary camels observed by Sahrawi pastoralists of Western Sahara

    Science.gov (United States)

    2013-01-01

    Background The traditional knowledge of local communities throughout the world is a valuable source of novel ideas and information to science. In this study, the ethnoveterinary knowledge of Sahrawi pastoralists of Western Sahara has been used in order to put forward a scientific hypothesis regarding the competitive interactions between camels and caterpillars in the Sahara ecosystem. Methods Between 2005 and 2009, 44 semi-structured interviews were conducted with Sahrawi pastoralists in the territories administered by the Sahrawi Arab Democratic Republic, Western Sahara, using a snow-ball sampling design. Results Sahrawi pastoralists reported the existence of a caterpillar-borne reproductive loss syndrome, known locally as duda, affecting their camels. On the basis of Sahrawi knowledge about duda and of a thorough literature review, we built the hypothesis that: 1) caterpillars of the family Lasiocampidae (genera Lasiocampa, Psilogaster, or Streblote) have sudden and rare outbreaks on Acacia treetops in the Western Sahara ecosystem after heavy rainfall; 2) during these outbreaks, camels ingest the caterpillars while browsing; 3) as a consequence of this ingestion, pregnant camels have sudden abortions or give birth to weaklings. This hypothesis was supported by inductive reasoning built on circumstantiated evidence and analogical reasoning with similar syndromes reported in mares in the United States and Australia. Conclusions The possible existence of a caterpillar-borne reproductive loss syndrome among camels has been reported for the first time, suggesting that such syndromes might be more widespread than what is currently known. Further research is warranted to validate the reported hypothesis. Finally, the importance of studying folk livestock diseases is reinforced in light of its usefulness in revealing as yet unknown biological phenomena that would deserve further investigation. Resumen ‘Todos lo saben’, menos el resto del mundo: el caso de un s

  13. ‘Everybody knows’, but the rest of the world: the case of a caterpillar-borne reproductive loss syndrome in dromedary camels observed by Sahrawi pastoralists of Western Sahara

    Directory of Open Access Journals (Sweden)

    Volpato Gabriele

    2013-01-01

    Full Text Available Abstract Background The traditional knowledge of local communities throughout the world is a valuable source of novel ideas and information to science. In this study, the ethnoveterinary knowledge of Sahrawi pastoralists of Western Sahara has been used in order to put forward a scientific hypothesis regarding the competitive interactions between camels and caterpillars in the Sahara ecosystem. Methods Between 2005 and 2009, 44 semi-structured interviews were conducted with Sahrawi pastoralists in the territories administered by the Sahrawi Arab Democratic Republic, Western Sahara, using a snow-ball sampling design. Results Sahrawi pastoralists reported the existence of a caterpillar-borne reproductive loss syndrome, known locally as duda, affecting their camels. On the basis of Sahrawi knowledge about duda and of a thorough literature review, we built the hypothesis that: 1 caterpillars of the family Lasiocampidae (genera Lasiocampa, Psilogaster, or Streblote have sudden and rare outbreaks on Acacia treetops in the Western Sahara ecosystem after heavy rainfall; 2 during these outbreaks, camels ingest the caterpillars while browsing; 3 as a consequence of this ingestion, pregnant camels have sudden abortions or give birth to weaklings. This hypothesis was supported by inductive reasoning built on circumstantiated evidence and analogical reasoning with similar syndromes reported in mares in the United States and Australia. Conclusions The possible existence of a caterpillar-borne reproductive loss syndrome among camels has been reported for the first time, suggesting that such syndromes might be more widespread than what is currently known. Further research is warranted to validate the reported hypothesis. Finally, the importance of studying folk livestock diseases is reinforced in light of its usefulness in revealing as yet unknown biological phenomena that would deserve further investigation. Resumen ‘Todos lo saben’, menos el resto del

  14. Sahra Tozunun Elemental Yapısının Bitkilerin Büyümesi Üzerindeki Göreceli Etkisinin İncelenmesi / Investigation of the Relative Effect of Sahara Dust's Elemental Structure on Plants' Growth

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    Ayşe Nihal Yücekutlu

    2012-12-01

    kalitesine olan katkısı, yapısında bulunan kullanılabilir demir üretiminin fidelerin açılımını tamamlamış genç yaprak segmentlerinin klorofil miktarındaki artış grafikleri, fide uzunlukları artış grafikleri (Hewitt besin çözeltisi ve deiyonize su uygulamasına göre ve bitki örneklerinin gelişim evrelerinde alınan fotoğrafları sunulacaktır. Investigation of the Relative Effect of Sahara Dust's Elemental Structure on Plants' Growth In the process of atmospheric convection, Sahara Desert dust, originated from North Africa, is the most significant source of mineral aerosol. In this research, behaviors of the desert soil samples, brought from Sahara, inside the cloud were practiced under laboratory conditions they were simulated and the effects of certain types of bread wheat (Triticum aestivum L. and durum wheat (Triticum durum L. grown inside germination tanks as receiving environment were analyzed. Seedling length (cm.seedling-1 and photosynthetic pigments [chlorophyll a, chlorophyll b, total chlorophyll (a+ b and carotenoids (c+x, mg ml-1 g Fresh Weight-1] have been determined. Plants were grown in controlled climate chamber, and the results were analyzed statistically. The results of this study indicate that, wheat cultivars fed by irradiated Saharan soil solution application length and its effects on photosynthetic pigments gave comparable results to Hewitt nutrient solution.

  15. A propósito del límite septentrional del imperio Incáico

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    Sergio Elías Ortíz

    1961-01-01

    Full Text Available Puesta nuevamente sobre el tapete de la discusión, por algunos americanistas, la cuestión de los límites extremos, hacia el Norte, de la expansión incaica, creemos del caso revisar las opiniones que se expusieron hace algunos años, cuando se suscitó el estudio del problema, Con motivo del trabajo de Monseñor Federico Lunardi, antiguo Auditor de la Nunciatura Apostólica en Colombia intitulado: "O Angasmayo ou os verdadeiros limites septentrionales do Imperio Incaico" (Río de Janeiro, 1935.

  16. Análisis de redes de parentesco y alianza entre caciques mapuches y tehuelches. Patagonia septentrional, siglo XIX

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    Julio Esteban Vezub

    2016-06-01

    Full Text Available Se revisita la historia política de uno los linajes de caciques más relevantes del norte de la Patagonia durante la expansión del estado nacional argentino de la segunda mitad del siglo XIX. Se vuelve sobre la heterogeneidad de fuentes (cartas de caciques, informes de autoridades y viajeros, listados de tropa indígena, etc. que ya había sido tratada con un método histórico narrativo. En esta ocasión se coteja este corpus con el Análisis de Redes Sociales (ARS, y los Sistemas de Información Geográfica (SIG, a los fines de interpretar los cambios de la topología relacional indígena y criolla en el contexto de emergencia del estado. Este objetivo se resuelve mediante la elaboración de grafos que representan la evolución de las redes parentales, y la estructura de poder indígena, ante una serie de eventos críticos entre 1856 y 1883. La hipótesis principal es que los linajes mapuches y tehuelches dieron el formato para la construcción de alianzas y filiaciones, las que tuvieron un carácter principalmente político por sobre los factores étnicos o de sangre. La experimentación destaca la importancia de combinar el análisis morfológico y estructural que permite el análisis de redes con la singularidad del comportamiento histórico de los actores

  17. Building thermal performance in Saharan climate

    Energy Technology Data Exchange (ETDEWEB)

    Belgaid, Brahim [Department of architecture, University of Batna, 05000- Batna (Algeria)

    2011-07-01

    The aim of this study is to present an analytical method of the contribution of the building's shape and orientation in the definition of a comfortable microclimate for the inhabitants of the warm regions of Algerian Sahara. Study is made by using the overheating, a concept allowing a fast estimation of the level of internal temperature. Calculations were performed for summer hot period for Biskra (a city of southern Algeria), situated in Sahara and characterized with a hot and dry climate. The influence of the shape and the orientation of the building are examined as a solution to improve the building's thermal performance.

  18. Dans la cuisine du partenariat. Retour sur les obstacles interculturels et institutionnels dans un projet de coopération universitaire franco-algérienne  In the kitchen of the partnership. A reflexive look at intercultural and institutional obstacles in a Franco-Algerian project of academic co-operation

    Directory of Open Access Journals (Sweden)

    Maurice Blanc

    2011-05-01

    Full Text Available Cet article analyse de manière réflexive une expérience de coopération universitaire franco-algérienne et il examine l’impact sur le partenariat des tensions produites par la mise à l’épreuve du terrain. Emboîté dans de multiples dispositifs, l’objet de la coopération concentre un faisceau d’attentes, aussi diverses que contradictoires, susceptibles de créer des tensions dans des négociations qu’il faut en permanence reprendre. L’article montre que l’approche par la transaction sociale est pertinente pour analyser des processus partenariaux qui passent par de la coopération conflictuelle et des arrangements informels. Deux obstacles majeurs apparaissent : les cercles vicieux bureaucratiques et les malentendus interculturels. Des transactions implicites et tacites permettent de débloquer lentement la situation.This paper makes a reflexive assessment of an experiment in Franco-Algerian academic co-operation. It addresses the impact on the partnership of the tensions which emerge at field level practice. Embedded in various institutional patterns, the aim of co-operation is caught between diverging and contradictory expectations, creating tensions which fuel never-ending negotiations. The paper highlights the relevance of a social transaction approach for the understanding of partnership processes which necessarily involve conflictual co-operation and informal arrangements. Two major obstacles emerge: bureaucratic vicious circles and intercultural misunderstandings. Implicit and/or tacit transactions can allow for the slow unfolding of situations.

  19. Etude de la diagenèse organique des séries paleozoiques du bassin de Sbaa (Algérie). Approche géochimique et pétrologique.

    OpenAIRE

    Laggoun-Défarge, Fatima

    1987-01-01

    The Sbaa basin is located in the West-Central Province of the Algerian Sahara. It essentially consists of Palaeozoic shales and sandstones ranging from Cambro-Ordovician to Namurian, overfolded by thin Mesozoic strata. An oil occurrence in the Sbaa sandstone Formation (Tournaisian age; 500 m deep, 22 millions tons of actual reserves) makes the basin distinctive in an area rich in gas fields. The geochemical and petrological studies of organic matter (OM) (160 samples from 9 wells) showed that...

  20. Valorization of Three Plant Species of Arid Areas in Biological Control of the Desert Locust Schistocerca gregaria. S. Messgo-Moumene, D. Merzouk, Z. Houmani, and K. Moumene. (Algeria)

    OpenAIRE

    Saïda Messgo-Moumene; Djamel -Eddine Merzouk; Zahia Houmani; Khaled Moumene

    2015-01-01

    The present work aims to evaluate the in vitro biocide effect of aqueous and ethanol extracts of plants collected from arid Algerian Sahara i.e. Calotropis procera, Schouwia purpurea, and Zizyphus lotus on the fifth larval instar (L5) of Schistocerca gregaria. These extracts obtained by decoction and solvent were tested respectively crude for the first one and at concentrations of 12.5% and 50% for the second one by contact and by ingestion. Significant mortality was recorded the ...